<PAGE>

                                                                   EXHIBIT 10.56

                             INDEX TO OFFICE LEASE
                         PLAZA 7000, LTD. (Lessor) and
                           DRKOOP.COM, INC. (Lessee)

<TABLE>
<CAPTION>
SECTION       TITLE                                                                                      Lease Page
<S>                                                                                                      <C>
1.1     The Leased Premises..............................................................................        3
1.2     Use..............................................................................................        3
1.3     Usable Area......................................................................................        3
1.4     Rentable Area....................................................................................        3
2.1     Base Rent and Additional Rents...................................................................        4
3.1     Date and Place of Payment........................................................................        4
3.2     Late Payments....................................................................................        4
3.3     Security Deposit.................................................................................        4
4.1     Term, Possession, and Anniversary................................................................        5
4.2     Acknowledgement of Lease.........................................................................        5
4.3     Delivery of Possession...........................................................................        5
5.1     Tenant Finish-Out................................................................................        5
6.1     Quiet Possession.................................................................................        5
7.1     Utilities and Services by Lessor.................................................................        5
7.2     Utilities and Services by Lessee.................................................................        6
7.3     Interruption of Utilities or Services............................................................        6
7.4     Extra Electricity................................................................................        6
7.5     Extra Heating or Air Conditioning................................................................        7
8.1     Maintenance and Repairs by Lessor................................................................        7
8.2     Maintenance and Repairs by Lessee................................................................        7
8.3     Telecommunications...............................................................................        7
9.1     Access, Keys, Locks, and Security................................................................        8
9.2     Parking..........................................................................................        8
10.1    Occupancy, Nuisance, and Hazards.................................................................        9
11.1    Taxes............................................................................................        9
12.1    Insurance........................................................................................        9
12.2    Waiver of Subrogation............................................................................        9
12.3    Hold Harmless....................................................................................       10
13.1    Alterations by Lessee............................................................................       10
13.2    Americans With Disabilities Act..................................................................       10
14.1    Removal of Property by Lessee....................................................................       11
15.1    Subletting and Assignment........................................................................       11
16.1    Destruction by Fire or Other Casualty............................................................       12
17.1    Condemnation.....................................................................................       12
18.1    Default by Lessor................................................................................       12
19.1    Default by Lessee................................................................................       12
20.1    Lien for Rent....................................................................................       14
21.1    Attorney's Fees, Interest, and Other Expenses....................................................       14
22.1    Nonwaiver........................................................................................       14
23.1    Building Rules...................................................................................       14
24.1    Transfer of Ownership by Lessor..................................................................       14
25.1    Mortgages........................................................................................       14
26.1    Surrender of Premises............................................................................       15
27.1    Holding Over.....................................................................................       15
28.1    Signs and Building Name..........................................................................       15
28.2    Relocation of Lessee.............................................................................       15
29.1    Notices..........................................................................................       15
</TABLE>

                                    Page 1

<PAGE>

<TABLE>
<S>                                                                                                             <C>
30.1    Estoppel Certificates............................................................................       16
31.1    Successors.......................................................................................       16
31.2    Leasing Agent Commissions........................................................................       16
32.1    Building Operating Expense.......................................................................       16
33.1    Representations and Warranties by Lessor.........................................................       16
34.1    Representations and Warranties by Lessee.........................................................       16
35.1    Place of Performance.............................................................................       16
36.1    Miscellaneous....................................................................................       17
37.1    Special Conditions...............................................................................       17
38.1    Exhibit List.....................................................................................       17
39.1    Lease Dates and Authority to Sign................................................................       17
EXHIBIT "A":          Floor Plan of Lessee's Office Space................................................       20
EXHIBIT "B":          Legal Description of Office Building...............................................       21
EXHIBIT "C":          Building Operating Expense Pass-Through Calculations...............................       22
EXHIBIT "D":          Acknowledgement of Lease...........................................................       24
EXHIBIT "E":          Work Letter........................................................................       26
EXHIBIT "F-1":        Office Building Parking Rules......................................................       30
EXHIBIT "F-2":        Office Building Rules..............................................................       31
EXHIBIT "G":          Estoppel Certificate...............................................................       34
EXHIBIT "H":          Office Lease Guaranty..............................................................       36
EXHIBIT "I":          Certificate of Corporate Resolution Authorizing Lease or Guaranty..................       37
EXHIBIT "J":          Special Conditions.................................................................       39
EXHIBIT "J-1":        Approved Plans and Specifications for Exterior Building Signage....................       42
EXHIBIT "J-2":        Schematic Drawing of Must-Take Expansion Space.....................................       43
EXHIBIT "K":          Hazardous Substances...............................................................       44
EXHIBIT "L":          Acknowledgment of Receipt of Agency Disclosure.....................................       45
EXHIBIT "M":          Renewal Option.....................................................................       47
EXHIBIT "N":          Right of First Offer...............................................................       49
EXHIBIT "O"           Satellite Dish/Antenna.............................................................       50
</TABLE>

                                    Page 2
<PAGE>

                                 OFFICE LEASE

                                  PLAZA 7000
                                  ----------


This is a Lease Agreement made and entered into between Lessor Name Specified in
                                                        ------------------------
Basic Lease Information #2, as "Lessor", and Lessee Name Specified in Basic
--------------------------                   ------------------------------
Lease Information #5, as "Lessee", whether one or more.
--------------------

1.1  The Leased Premises.

Lessor hereby leases to Lessee, and Lessee hereby leases from Lessor the "Leased
Premises" which consists of "Lessee's Office Space" and "Common Areas" as
defined below.

(a)  Lessee's Office Space.  "Lessee's Office Space", to which Lessee shall have
     exclusive use rights, consists of suite(s) Specified in Basic Lease
                                                ------------------------
Information #3, representing the office space outlined and shaded on the floor
--------------
plan contained in Exhibit "A".  Such space is located in the building on a tract
                  -----------
of land, legally described by lot and block or metes and bounds in Exhibit "B".
                                                                   -----------
The street address of the building is Specified in Basic Lease Information #1.
                                      ---------------------------------------

(b)  Common Areas.  The "common area", to which Lessee shall have non-exclusive
use rights, consists of (1) the interior common area located in the above
described building, i.e., areas normally accessible to tenants such as the
hallways, stairwells, elevators, lobby, restrooms, and snack bar areas, and (2)
the exterior common area located outside the building on the above described
land, i.e., loading areas, sidewalks, driveways, parking garage, parking areas,
and other open areas (if any), subject to paragraph 9.2 on parking.

1.2  Use.

Lessee's Office Space may be used only for general office purposes and other
uses incident thereto.  In no event may the Lessee's office space, or any
portion thereof, be used or leased for an "executive suites" or "serviced
                                          ------------------    ---------
business center" operation.  The name of Lessee's business is Specified in Basic
----------------                                              ------------------
Lease Information #5.
--------------------

1.3  Usable Area.

Lessee's approximate "usable area" is Specified in Basic Lease Information #4
                                      ---------------------------------------
and is subject to verification by Lessee's architect.  It is the office space
outlined and shaded in Exhibit "A".  Such area is measured from the interior of
                       -----------
the exterior walls and the exterior glass lines of the building to the middle of
the remaining perimeter walls of the office space, in accordance with applicable
BOMA standards.  Prior to taking occupancy of the Leased Premises Lessee shall
have the right to have a registered architect verify the measurement of Lessee's
Office Space and the rentable and useable square footage associated therewith.
In the event that it is determined by such remeasurement that the Leased
Premises is less than the area stated in Basic Lease Information #4, and the
                                         --------------------------
results of such remeasurement are agreed to by Lessor's architect [such
agreement not to be unreasonably withheld and in any event to be based on the
applicable BOMA standard (currently ANSI version Z65-1, 1996)], the rent payable
hereunder shall be appropriately adjusted during the term and extended term
hereof.  Any such adjustment must be made and agreed to by Lessor and Lessee, if
at all, prior to Lessee taking occupancy of the Leased Premises.  Upon taking
occupancy of the Leased Premises, Lessee shall be required to stipulate and
agree to the rentable area of the Leased Premises by executing Exhibit "D"
                                                               -----------
attached hereto which will constitute the irrevocable waiver by Lessee of any
challenge to the measured size of the Leased Premises.

1.4  Rentable Area.

Lessee's approximate "rentable area" is Specified in Basic Lease Information #4.
                                        ---------------------------------------
It consists of Lessee's "usable area" as defined above, plus Lessee's prorata
share of the building common areas as set forth in Basic Lease Information #4.
                                                -----------------------------
Building common areas are defined as all corridors, restrooms, common vending
machine areas, building equipment rooms, telephone closets, janitor closets,
enclosed lobby, entrance areas, and other public areas in the building,
excluding elevator shafts, stairwells, vertical chases, and enclosed parking
areas.


2.1  Base Rent and Additional Rents.

                                    Page 3
<PAGE>

Lessee shall pay to Lessor a "base rent" Specified in Basic Lease Information #7
                                         ---------------------------------------
per calendar year, which amounts to the sum(s) Specified in Basic Lease
                                               ------------------------
Information #7 per calendar month.  Such base rent is equivalent to the sums
--------------
Specified in Basic Lease Information #7 per square foot per year for Lessee's
---------------------------------------
rentable area.  The base rent is subject to adjustment as provided in paragraph
32.1.  Additional rent (representing Lessee's prorata share of building
operating expenses over the expense stop Specified in Basic Lease Information #8
                                         ---------------------------------------
shall be paid in accordance with paragraph 32.1.  Building operating expenses up
to such expense stop amount shall be paid by Lessor.


3.1  Date and Place of Payment.

The monthly rent and one-twelfth of Lessee's share of estimated building
operating expenses under paragraph 32.1 shall be due on the first day of each
calendar month without demand.  Partial months shall be prorated.  All rent and
other sums are due in the county where the building is located at the address
designated by Lessor from time to time.  All sums due by Lessee are without
right of setoff or deduction.  Monies mailed are considered timely paid only if
received by Lessor by the due date; however rents postmarked one or more days
before due date and received after the due date shall be considered as timely
received by Lessor.  Rent and late payment charges shall be paid without notice
or demand.  All other sums shall be due upon delivery of written notice in
accordance with paragraph 29.1.

3.2  Late Payments.

If any rent payment or other sum due by Lessee to Lessor is received and
accepted by Lessor later than five (5) days after its due date, Lessee shall pay
a late charge of 5% of such rent payment or other sum.  Late charges shall be
considered liquidated damages for Lessor's time, inconvenience and overhead
(except for attorneys fees and litigation costs) in collecting late rent.
Lessor's acceptance of late rent or other sum shall not constitute permission
for Lessee to pay the rent or other sum late thereafter and shall not constitute
a waiver of Lessor's remedies for subsequent late payments.  Late payment
charges are due immediately upon notice or demand.  All payments shall be by
check or money order on a local bank, not cash.  For each returned check, Lessee
shall pay all applicable bank charges incurred by Lessor plus $50.00.  Payments
of any kind received by Lessor on behalf of Lessee may be applied at Lessor's
option to nonrent items that Lessee is then obligated to pay hereunder, then to
rent.  Payment of rent by Lessee shall be an independent covenant.  If Lessee
has not timely paid rentals and other sums due on two or more occasions, or if a
check from Lessee is returned for insufficient funds or no account, Lessor may
for the next 12 months require that all rent and other sums due be paid by
cashier's check, certified check, or money order, without prior notice.

3.3  Security Deposit.

At the time of execution of this lease, Lessee shall deposit with Lessor cash in
the sum Specified in Basic Lease Information #10 to secure performance of
        ----------------------------------------
Lessee's obligations under this lease.  Lessor shall have a lien on the security
deposit for that purpose.  If Lessee fails to pay rent or other sums when due
under this lease, Lessor may apply any cash security deposit toward amounts due
and unpaid by Lessee.  In lieu of a cash security deposit, Lessee may furnish
Lessor at time of execution of this lease an irrevocable letter of credit in the
sum Specified in Basic Lease Information #10-c on a financial institution in
    ------------------------------------------
Austin, Texas. The issuing bank must be reasonably acceptable to Lessor and the
letter of credit must be negotiable in Austin, Texas.  The Letter of Credit
shall name Lessor as the Beneficiary thereof.  The Letter of Credit shall
provide that Lessor may draw all or a portion of the entire face amount of the
Letter of Credit upon the presentation of the original of the Letter of Credit
together with a sworn affidavit by Lessor (or an officer of Lessor) stating that
Lessee has failed to pay base rent, additional rent or other sums due hereunder
when due and as a result thereof is in default hereunder and that all cure
periods relating to such default have expired.  Notwithstanding the foregoing,
Lessor shall only be entitled to draw against the Letter of Credit the amount
required to pay all rent or other sums which is/are then due and owing at the
time of such draw unless within twelve (12) months after any such draw another
event of default occurs pursuant to which Lessor is entitled to draw against the
Letter of Credit, in which case Lessor may draw the entire amount of the Letter
of Credit.  Further, Landlord shall not be entitled to draw against the Letter
of Credit unless the amount of the default is at least $3,000.00.  The Letter of
Credit shall also provide that it may be drawn in full by Lessor in the same
manner if at any time prior to the expiration of this Lease the Letter of Credit
is within thirty (30) days of expiring and a replacement or extension thereof
has not been furnished to Lessor.  The Letter of Credit, including, without
limitation, the form thereof, and all extensions and renewals thereof, shall
otherwise be reasonably acceptable to Lessor in all respects.  This Section
3.3 is subject in all respects to the special conditions set forth in paragraph
10 of Exhibit "J" attached hereto.
      -----------

If Lessee furnishes a letter of credit in lieu of a cash security deposit,
Lessee covenants to continuously keep the Letter of Credit in full force and
effect and failure to do so shall constitute an Event of Default hereunder.  The
Letter of Credit shall be assignable

                                    Page 4
<PAGE>

and transferrable to Lessor's mortgage lender and to a purchaser of the
Property. In the event Lessor ever draws on the Letter of Credit, Lessor may
thereafter retain all proceeds thereof in the form of cash in the same manner as
if such funds had been originally deposited with Lessor as a cash security
deposit; provided, however, that Lessor will accept a replacement Letter of
Credit and will refund to Lessee all unapplied portions of the proceeds of the
negotiated Letter of Credit after a period of six (6) months elapses during
which Lessee is not late in the payment of rent or other charges due hereunder
and during which Lessee is not otherwise in default. Lessee shall immediately
restore the security deposit to the amount then required to be maintained under
the Lease after any portion of it is applied to amounts due and unpaid by
Lessee.

4.1  Term, Possession, and Anniversary.

The initial lease term shall be for eighty-five (85) calendar months from the
"Commencement Date", plus the remainder of the last month.  The "Commencement
Date" of this lease shall be the earlier of (a) the date Lessee opens for
business in Lessee's Office Space, or (b) five (5) days after Lessor delivers
possession of Lessee's Office Space to Lessee and the Interior Improvements are
substantially complete.

4.2  Acknowledgement of Lease.

Upon commencement of this lease, Lessor and Lessee shall execute a recordable
acknowledgment of this lease which is attached as Exhibit "D" and which will
                                                  -----------
confirm the Commencement Date, ending date, annual anniversary date of the
lease, and rentable square footage in Lessee's Office Space.

4.3  Delivery of Possession.

Lessor shall deliver keys and/or access cards or codes and possession of
Lessee's Office Space to Lessee on the lease Commencement Date stated in
paragraph 4.1 unless otherwise agreed in writing by the parties.  Lessee shall
not be liable for rent until Lessor delivers possession of the Leased Premises
to Lessee.  If there is a delay in delivery of possession, rent shall be abated
until Lessee's Office Space is ready for occupancy; and neither Lessor nor
Lessor's agents shall otherwise be liable for any damages; and the lease shall
not terminate.  Construction of Interior Improvements (as such term is defined
in Exhibit "E" attached hereto) shall, comply with the approved Interior
   -----------
Improvements Plans; provided, however, that Lessor's approval of the Interior
Improvement Plans (as such term is defined on Exhibit "E" attached hereto) shall
                                              -----------
create or impose no liability or responsibility on Lessor for their
completeness, design sufficiency or compliance with all applicable laws, rules
and regulations of governmental agencies or authorities.

5.1  Tenant Finish-Out.

     (Check one):
     ________  (a) Lessor shall provide no tenant finish-out or improvements
               since Lessee has taken Lessee's Office Space "as is".
         X     (b)  Lessor shall perform any special construction described in
     --------
               Exhibit "E".  Costs of tenant finish-out or special
               construction shall be paid for pursuant to such exhibit.

6.1  Quiet Possession.

If Lessee is current and in compliance with all of Lessee's obligations under
this lease, Lessee shall be entitled to peaceful and quiet possession and
enjoyment of Lessee's Office Space, subject to the terms and conditions of this
lease.  Lessee shall have access to the building parking garage, if applicable
and common parking areas at all times, subject to parking fees and the rules
referred to in paragraphs 9.2 and 23.1.  Lessor shall make diligent efforts to
have all other tenants in the building comply with building rules.  Otherwise,
failure of other tenants to comply with such rules shall not be considered a
default by Lessor.  Construction noise or vibrations shall not be considered a
default by Lessor provided, however, that Lessor shall make commercially
reasonable efforts to minimize construction noise and construction vibrations
during standard business hours.

7.1  Utilities and Services by Lessor.

Except where otherwise stated in this lease, Lessor shall pay for and furnish in
a timely and diligent manner to Lessee the following utilities (subject to
Lessee being required to pay for same directly to the utility provider) and
services and no others, subject to paragraph 32.1 regarding Lessee's payment of
Lessee's prorata share of building operating expenses.

(a)  air conditioning and heating as reasonably required for comfortable use and
     occupancy under normal office conditions from 7:00 a.m. to 7:00 p.m. on
     Monday through Friday, and from 8:00 a.m. to 1:00 p.m. on Saturday, but not
     on

                                    Page 5
<PAGE>

     Sunday, New Year's Day, Memorial Day, July 4th, Labor Day, Thanksgiving
     or Christmas so long as these times and dates comply with present and
     future governmental laws, rules and regulations to which that Lessor is
     required to adhere, including utilities such as electricity, gas, and water
     necessary for operation of same;
(b)  water and wastewater services for common areas;
(c)  janitorial and cleaning services for the building five days a week
     consistent with the maintenance of a "Class A" office building in the
     Austin, Texas area;
(d)  electricity for standard office equipment and lighting;
(e)  trash collection services (dumpster or garbage cans);
(f)  pest control services as needed in the reasonable judgment of Lessor;
(g)  landscaping and parking lot maintenance services;
(h)  repair and maintenance services pursuant to paragraph 8.1;
(i)  replacement of fluorescent light bulbs and ballasts in building standard
     lighting fixtures and, upon the request of Lessee from time to time,
     replacement of Lessee supplied light bulbs in nonstandard light fixtures
     (but not moveable lamps); and
(j)  elevator service, if there is an elevator in the building.

Lessor is not responsible for the safety or security of Lessee or any of
Lessee's employees or invitees, nor is Lessor responsible for providing any
security personnel or patrols to protect the person or property of Lessee or any
of Lessee's employees or invitees.  Should Lessor engage any security personnel
or patrols at any time during the term of this Lease, such personnel and patrols
shall be for the protection of Lessor's property only.

7.2  Utilities and Services by Lessee.

Subject to Section 7.4, if applicable, Lessee shall pay for all utilities and
services not expressly furnished by Lessor under paragraph 7.1.  Lessee shall
pay for all electricity consumed through any individual electrical meter(s) or
submeter(s) serving Lessee's Office Space.  Costs of such utilities are not
considered building operating expenses to be allocated among all tenants under
paragraph 32.1.  Service through individual electrical meters which exclusively
serve Lessee's Office Space shall be in the name of Lessee.  Lessor reserves the
right to submeter electricity and/or water.  Any electricity or water
submetering shall be billed to and paid by Lessee at Lessor's average cost per
KWH or gallon, and no more.  If the water bill from the utility company includes
wastewater charges, Lessee's liability for water submetering shall include
corresponding wastewater costs (if any).

7.3  Interruption of Utilities or Services.

Except as otherwise provided in this Section 7.3, temporary interruption or
malfunction of utilities, services, and/or telephones shall not render Lessor
liable for damages, rent abatements, or release of any Lessee obligation.
Lessor shall use diligent efforts to have such utilities and services restored
as soon as reasonably possible.  Anything in the Lease to the contrary
notwithstanding, if at any time the Leased Premises shall be untenantable or
Lessee is unable to conduct its full and ordinary operations at the Leased
Premises for a period of five (5) or more consecutive days because of any
interruption or malfunction of utilities, services, and/or telephones (which
interruptions are not specific to Lessee's telephone system), rent shall be
abated commencing on the sixth (6th) day of such interruption or malfunction
until full restoration of utilities, services and/or telephones, as the case may
be.  In the event any such interruption or malfunction shall continue for a
period of thirty (30) or more consecutive days or forty-five (45) or more days
in any calendar year, Lessee shall have the right to terminate this Lease within
ten (10) days after the expiration of such thirty or forty-five day period, as
applicable, but not thereafter, upon written notice to Lessor.

7.4  Extra Electricity.

There shall be no extra electricity charges for typewriters, facsimile machines,
word processors, personal computers, computer servers, dictating equipment,
adding machines, desk top calculators, lamps, or other standard 110 volt office
equipment, and 220 volt copiers.  However, Lessee shall pay Lessor monthly, as
billed, for charges which are separately metered or which Lessor may reasonably
compute for electricity utilized by Lessee for the following purposes: x-ray
machines, hotplates, electric heaters, 220 volt equipment other than 220 volt
copiers, computers (other than desktop, personal or word processor computers and
computer servers), or other electrical service not standard for the building.

7.5  Extra Heating or Air Conditioning.

If Lessee requests air conditioning or heating after the hours as set forth in
paragraph 7.1(a), Lessor may charge Lessee the extra hourly fee specified in
                                                                ------------
Basic Lease Information #12c for after-hour air conditioning or heating.
----------------------------

                                    Page 6
<PAGE>

8.1  Maintenance and Repairs by Lessor.

Lessor shall operate and maintain the building in which the Leased Premises are
located and all facilities relating thereto in a "Class A" manner consistent
with the appearance and operation and maintenance standards of other Class "A"
suburban office buildings in the Austin, Texas area.  Lessor shall repair and/or
replace, as needed, the following items as a building expense under paragraph
32.1, so long as they are building standard items: light bulbs, ballasts, and
fixtures; plumbing; hardware; appliances; doors; and wall and window coverings.
Lessor shall use diligence to provide for the reasonable cleaning, maintenance,
and repair of common areas, reconnection of interrupted utilities or services,
subject to any reimbursement obligations of Lessee under paragraph 8.2.  Lessor
shall also maintain and keep in good repair the roof, outside walls, foundation,
exterior window and exterior door frames and structural portions of the building
and all electrical, mechanical and HVAC systems servicing the common areas and
the Leased Premises.  Lessor shall also maintain the exterior areas of the
building, including the landscaping, walkways and parking areas in a neat and
clean condition.  Lessor may rekey at any time.  Lessor may temporarily close
any part of the common facilities if reasonably necessary for repairs or
construction provided that Lessee at all times has continuous and uninterrupted
use of the Leased Premises.  Repairs and maintenance shall be in accordance with
applicable governmental requirements and shall be completed in a good and
workmanlike fashion.

8.2  Maintenance and Repairs by Lessee.

Lessee shall promptly reimburse Lessor for the cost of repairing or replacing
non-building standard items inside Lessee's office space and the cost of
repairing or replacing damage which is caused inside Lessee's office space by
Lessee, Lessee's agents, employees, family, or licensees, invitees, visitors, or
customers or outside Lessee's office space by Lessee or Lessee's employee's,
agents, or contractors; provided however, that before any such repairs or
replacements are made by Lessor, Lessor shall first give Lessee written notice
of the necessity for any such repairs or replacements and allow Lessee thirty
(30) days from such notice for the Lessee to make such repairs and replacements.
Lessor shall have the right of approval of all repairmen or maintenance
personnel, which approval shall not be unreasonable withheld.  Lessee shall not
damage or allow other persons listed above to damage any portion of the Leased
Premises.  Lessee shall pay for replacement of all non-building standard light
bulbs and for unstopping any drains or water closets in Lessee's office.  If
Lessee or Lessee's workmen or contractors are permitted to repair, alter, or
modify Lessee's office space, Lessee shall warrant that no mechanic or
materialman's lien shall be filed against the Leased Premises and that all such
contractors shall provide evidence of liability insurance as required by Lessor.
All such work shall be in accordance with applicable governmental requirements.
In the event a mechanics or materialman's lien is filed, Lessee agrees to obtain
a release of such lien within ten (10) days after Lessee receives notice of the
filing of the same or to provide a bond within such ten (10) day period
indemnifying Lessor and the building against such lien in accordance with the
applicable provisions of Chapter 53 of Subchapter H, Texas Property Code.
Lessee's failure to remove any such mechanics or materialman's liens within such
ten (10) day period will constitute an event of default hereunder
notwithstanding any provisions for notice or opportunity to cure contained in
this lease to the contrary.

8.3  Telecommunications.

All telecommunications equipment necessary to serve Lessee shall be located in
Lessee's office space and paid for by Lessee, or, at Lessor's option and at
Lessee's expense, in a lockable enclosure in a common area location designated
by Lessor.  Lessee may not require Lessor to install or allow others to install
telecommunication lines or equipment elsewhere in the building.  Lessee
expressly waives any rights to require same under any circumstances.  Lessee
shall have access at all times to Lessee's telecommunications equipment that is
located outside the Lessee's office space.

9.1  Access, Keys, Locks, and Security.

(a)  Access.  Lessee shall have access to Lessee's office space at all times.
Lessor shall have access to Lessee's office space at reasonable times for
reasonable business purposes upon prior notice to Lessee except notice shall not
be necessary in the event of an emergency threatening life or property or the
lawful exercise of Lessor's remedies in case of default by Lessee. Lessor may
show Lessee's office space ninety (90) days before the lease expiration date or
the date Lessee gives notice to vacate, whichever is earlier

(b)  Keys.  Lessor shall furnish Lessee up to two hundred (200) keys or access
codes or cards for Lessee's office space, up to two hundred (200) keys or access
codes or cards for the main exterior entry doors of the building if such door is
locked after hours, and two (2) keys or access codes or cards to Lessee's
mailbox in the building. At Lessee's request additional or

                                    Page 7
<PAGE>

replacement keys or access codes or cards shall be furnished for a $10.00
refundable deposit. Lessor shall not be liable for risk of loss resulting from
Lessee's keys, access codes, or cards being stolen, lost or used by unauthorized
persons. Lessor reserves the right to rekey or change locks for security reasons
if new keys are timely furnished to Lessee.

(c)  Locks.  Lessee may not add locks, change locks, or rekey locks without
written permission of Lessor. Locks may be changed at Lessee's request and
expense. If locks to the office space are changed, Lessor may specify kind and
brand of locks, placement, installation, master key compatibility, etc. If
Lessee or any of Lessee's employees lock themselves out of Lessee's suite, said
person must call a fellow-employee to gain access. Neither Lessor nor the
management company personnel are authorized to unlock a door after hours except
for emergency or cleaning purposes.

(d)  Security.  Lessor shall have no duty to provide any security services of
any kind unless expressly provided in this lease. Lessor shall not be liable to
Lessee or Lessee's employees, family, customers, invitees, contractors, or
agents for injury, damage, or loss to person or property caused by criminal
conduct of other persons, including theft, burglary, assault, vandalism or other
crimes other than injury, damage or loss caused by Landlord's gross negligence,
willfull actions or breach of this Lease. Lessee shall lock its office space
doors when the last person leaves such office space for the day.

     Any security services which are provided by Lessor shall be for the
protection of Lessor's property only.

9.2  Parking.

(a)  All parking for the building is contained in the surface parking lot and
the parking structure adjacent to the building. Lessee, Lessee's employees,
visitors, invitees, and customers shall only be entitled to use the number of
parking spaces at any time as are allocated to the Leased Premises as designated
in Basic Lease Information #9. All parking is unreserved unless otherwise
   --------------------------
designated. If applicable, Lessee and Lessee's employees and customers shall
have exclusive right to park in any reserved parking spaces leased to Lessee
pursuant to a separate written agreement. Otherwise, none of Lessee, Lessee's
employees, visitors or customers may park in reserved parking spaces. Any
reserved parking spaces leased to Lessee shall be governed the terms and
conditions of such separate, signed written agreement.

(b)  Lessor shall have sole control over the parking of all vehicles (including
but not limited to cars, trucks, recreational vehicles, trailers, bicycles and
motorcycles) and shall designate parking areas and building service areas.
Parking rules are contained in the attached Exhibit "F-1". If vehicles are
                                            -------------
parked in violation of Lessor's parking rules or in violation of state statutes,
Lessor may exercise vehicle removal remedies under Article 6701g-2 of the Texas
Civil Statutes upon compliance with statutory notice.

(c)  Lessee hereby acknowledges that Lessee is allocated only the amount of
parking set forth in Basic Lease Information #9 attached to this Lease. The
                     --------------------------
foregoing shall not be construed to prohibit Lessee from occupying Lessee's
office space at a density of more than one person per 250 rentable square feet,
however, Lessee shall at all times be and remain responsible for compliance with
all laws, codes, statutes, rules and regulations of all governmental authorities
with jurisdiction over the Leased Premises relating to maximum density of
occupancy of the Leased Premises and Lessee shall not be entitled to exceed its
hereinabove parking ratio. In the event the use of the parking facilities by
Lessee or Lessee's employees at any time exceeds the allocation set forth in
Basic Lease Information #9, Lessor shall have the right to require Lessee to
--------------------------
make alternate provisions off-site, at Lessee's sole cost and expense, for
all of such excess parking.

10.1 Occupancy, Nuisance, and Hazards.

Lessee's office space shall be occupied only by Lessee or Lessee's employees and
shall not be left entirely vacant or used exclusively for storage.  Lessee and
Lessee's agents, employees, family, licensees, invitees, visitors, and
contractors shall comply with all federal, state, and local laws relating to
occupancy or to criminal conduct while such persons are on the Leased Premises.
Lessee and the persons listed above shall not (1) use, occupy, or permit the use
or occupancy of the Leased Premises or any purpose which is directly or
indirectly forbidden by such laws or which may be dangerous to life or property,
(2) permit any public or private nuisance, (3) disturb the quiet enjoyment of
other tenants, (4) do anything which might emit offensive odors or fumes, (5)
make undue noise or vibrations, (6) permit anything which would cancel insurance
coverage or increase the insurance rate on the building or contents, or (7)
otherwise damage the Leased Premises.

                                    Page 8
<PAGE>

11.1 Taxes.

Lessor shall be responsible for payment of all taxes and assessments against the
building subject to Lessee's obligation to pay Lessor for Lessee's share
thereof, on a prorata square foot basis, as additional rent pursuant to
paragraph 32.1.  Lessee shall timely pay all taxes assessed against Lessee's
furniture, equipment, fixtures, or other personal property in Lessee's office
space.

12.1 Insurance.

Lessor and Lessee shall comply with the respective insurance obligations as set
forth below:

(a)  Lessor.  Lessor shall maintain (1) fire and extended coverage insurance,
including vandalism and malicious mischief, on the office building, and (2)
comprehensive general liability insurance. The amounts shall be as required by
Lessor's mortgagee or as Lessor may deem reasonably appropriate, whichever is
greater. Lessor shall have no responsibility to maintain fire and extended
coverage insurance on Lessee's contents. The portion of Lessor's insurance
premiums reasonably due to Lessee's acts or omissions or Lessee's special use,
improvements, or tenant finish-out (over and above Lessee's normal use as
contemplated in paragraph 1.1(a)) shall be paid for by Lessee.

(b)  Lessee.  Lessee shall provide Lessee's own public liability insurance for
its operations on the Leased Premises in an amount equal to the minimum "primary
coverage" amount required by Lessor's insurance carrier as a condition for
purchasing umbrella liability insurance by Lessor. In no event shall such
coverage be less than $1,000,000. Upon written notice by Lessor to Lessee, such
dollar amount of Lessee's liability policy shall be increased by the amount of
any increase required by Lessee's carrier for "primary coverage" under an
umbrella liability policy. Lessee is encouraged to maintain fire and extended
coverage insurance (including theft, vandalism and malicious mischief) on the
contents in Lessee's office space, including fixtures, furniture, equipment,
supplies, inventory, and other personal property. Such property is not covered
by Lessor's insurance.

(c)  Insurance certificates.  Lessee shall provide Lessor with a certificate of
Lessee's insurance or a copy thereof as required above within 7 days after
Lessee initially occupies Lessee's office space or any portion thereof. Lessor
and Lessor's managing agent (if any) shall be named as additional insureds on
Lessee's liability insurance policy. Upon written request by Lessor, changes in
the name of Lessor or Lessor's managing agent shall be reflected on such
certificate.

(d)  Notice from Lessee's Insurance Carrier.  All policies of insurance to be
provided by Lessee shall contain a provision (to the extent legally permitted)
that the insurance company shall give Lessor at least 10 days' written notice to
Lessor, in advance of (1) any cancellation or non-renewal of the policy, (2) any
reduction in the policy amount, and (3) any deletion of additional insureds.

12.2 Waiver of Subrogation.

(a)  If waiver of subrogation is not contained in the form language of the
insurance policy, Lessor and Lessee may require that the other party's fire,
casualty, or liability insurance policy contain a waiver of subrogation clause.
For purposes of waiver of subrogation, Lessor and Lessee release each other and
their respective officers, directors, employees, and agents from any claims
based on negligence or otherwise, for loss, damage, or injury which occur
hereafter and are insured against under insurance policies carried by Lessor
and/or Lessee. The foregoing shall not apply to losses, damages, or injuries
that are in excess of policy limits or that are not covered due to a deductible
clause in the policy or due to the fact that the insurer has not agreed to waive
its right of subrogation.

(b)  Upon written request, Lessor and Lessee shall furnish to each other copies
of the policies of insurance referred to in this lease, including any waivers
of subrogation, or satisfactory evidence of same.

12.3 Hold Harmless.

TO THE EXTENT THAT IT IS NOT COVERED BY LESSOR OR LESSOR'S INSURANCE, LESSEE
SHALL INDEMNIFY LESSOR FOR AND SHALL HOLD LESSOR HARMLESS FROM, ALL FINES,
CLAIMS, LIABILITIES AND SUITS (INCLUDING COSTS AND EXPENSES OF DEFENDING AGAINST
SAME) RESULTING FROM ANY BREACH OR NONPERFORMANCE OF THE LEASE BY LESSEE OR
LESSEE'S AGENTS, EMPLOYEES, FAMILY, LICENSEES, OR INVITEES.  TO THE EXTENT THAT
IT IS NOT COVERED BY LESSEE'S INSURANCE, LESSOR SHALL INDEMNIFY LESSEE FOR AND
SHALL HOLD LESSEE HARMLESS FROM ALL FINES, CLAIMS, LIABILITIES AND SUITS

                                    Page 9
<PAGE>

(INCLUDING COSTS AND EXPENSES OF DEFENDING AGAINST SAME) RESULTING FROM ANY
BREACH OR NONPERFORMANCE OF THE LEASE BY LESSOR OR LESSOR'S AGENTS, EMPLOYEES,
FAMILY, LICENSEES, OR INVITEES.  TO THE EXTENT THAT IT IS NOT COVERED BY LESSOR
OR LESSOR'S INSURANCE, LESSOR AND LESSEE SHALL NOT BE LIABLE TO THE OTHER OR THE
OTHER'S AGENTS, EMPLOYEES, OR FAMILY FOR ANY DAMAGE TO PERSONAL PROPERTY
RESULTING FROM ANY ACT, OMISSION, OR NEGLIGENCE OF ANY OTHER TENANT, VISITOR OR
OCCUPANT OF THE OFFICE BUILDING.

13.1 Alterations by Lessee.

Lessee may not make any alterations, improvements, doorlock changes, or other
modifications of any kind to the Leased Premises without Lessor's written
consent, which consent will not be unreasonably withheld so long as alterations,
improvements, changes or modifications are (i) cosmetic, and not structural, and
(ii) not visible from outside the Leased Premises.  Consent for governmentally
required changes may not be unreasonably withheld.  "Alterations" include but
are not limited to improvements glued, screwed, nailed, or otherwise permanently
attached to the building, structural changes, roof and wall penetrations, and
all plumbing, electrical, and HVAC changes, but shall not include and Lessor's
consent shall not be required for the installation of Lessee's trade fixtures or
for normal interior decorative items at the Leased Premises (attachment of
pictures, picture frames and wall hangings to walls, etc.).  Requests for
Lessor's approval shall be in writing and shall be detailed to Lessor's
reasonable satisfaction.  The foregoing shall be done only by Lessor's
contractors or employees or by third parties approved by Lessor in writing.
Lessor shall charge a supervision/construction management fee equal to five
percent (5%)of the total cost of any such alterations, improvements, changes or
modifications which will be payable by Lessee prior to the commencement of the
work.  Lessee shall pay in advance for any requested alterations, improvements,
lock changes, or other modifications which are approved and performed by Lessor.
If same are performed by Lessee with Lessor's permission, Lessee shall not allow
any liens to be placed against the buildings as a result of such additions or
alterations.  If any such alterations, improvements, changes or modifications
are performed by Lessee or by Lessee's contractors and any mechanic's or
materialman's liens are filed against the Property in connection therewith,
Lessee agrees to obtain a release of such lien within ten (10) days after Lessee
receives notice of the filing of the same or to provide a bond within such ten
(10) day period indemnifying Lessor and the building against such lien in
accordance with the applicable provisions of Chapter 53, Subchapter H, Texas
Property Code.  Lessee's failure to remove any such mechanic's or materialman's
liens within such ten (10) day period will constitute an event of default
hereunder, notwithstanding any provisions for notice or opportunity to cure
contained elsewhere in this Lease to the contrary.  Alterations, improvements,
and modifications done at Lessee's request shall comply with all applicable
laws.  Changes in Lessee's alterations or improvements in Lessee's space which
may be later required by governmental action shall also be paid for by Lessee.

13.2 Americans With Disabilities Act.

Lessor shall at all times be responsible for any requirements under the
Americans with Disabilities Act or similar state or local laws as relate to any
common area restrooms, entrance and exit doorways and elevators and to
structural building items that Lessor is required to maintain under the terms of
this lease and as to the restroom facilities installed by Landlord in the Leased
Premises.  Lessor agrees to indemnify Lessee for any liability Lessee shall
incur as a result of Lessor's failure to comply with the provisions of this
paragraph.  Lessee agrees to cooperate fully with Lessor to enable Lessor to
timely comply with the provisions of this paragraph and to immediately forward
to Lessor any notice Lessee receives regarding complaints, injuries, or claims
by anyone claiming that those items which are the responsibility of Lessor do
not comply with the provisions of the Americans with Disabilities Act.  Lessee
shall be responsible for any requirements under such architectural barrier laws
as they relate to the design and use of Lessee's office space (other than the
restroom facilities installed by the Landlord in the Leased Premises),
including, but not limited to, the positioning of Lessee's furnishings within
the office space.  Lessee agrees to indemnify Lessor for any liability Lessor
shall incur as a result of Lessee's failure to comply with the provisions of
this paragraph.

14.1 Removal of Property by Lessee.

Lessee shall remove its trade fixtures, furniture equipment, and all other
personal property of Lessee (including kitchen appliances) prior to the end of
the lease term.  Lessee shall pay all costs of removal.  Lessee shall have no
rights to property remaining on the Leased Premises after the expiration or
termination of this lease or Lessee's right of possession of the Leased Premises
hereunder, howsoever the same may be brought about.  Lessee may not remove any
alterations as defined in paragraph 13.1 or improvements such as wall-to-wall
carpeting, built-in book shelves, window coverings, drapes, cabinets, paneling,
counters, kitchen or breakroom built-ins, shelving, wall covering, and anything
else attached to the floor, walls, or ceilings (other than Lessee's furniture,
removable trade fixtures, and equipment).  If Lessor requests in writing, Lessee
shall, immediately prior to moving out, remove any alterations, fixtures,
equipment, and other property installed by Lessee.  Lessee shall pay for
cleaning or

                                    Page 10
<PAGE>

repairing damage caused by Lessee's removal of any property.

15.1 Subletting and Assignment.

Lessee may not sublet, assign, pledge, or mortgage this lease and may not grant
licenses, commissions, or other rights of occupancy to all or any portion
thereof or any part of the Leased Premises without Lessor's prior written
approval which shall not be unreasonably withheld.  Lessor agrees to approve or
reject any Lessee request to sublet, assign, pledge or mortgage this Lease
within fifteen (15) days of Lessee's written request therefor, and in the event
Lessor does not approve or reject such request in accordance with this paragraph
on or before the end of such 15 day period, Lessor shall be deemed to have
consented to such subletting, assignment, pledge or mortgage.  A potential
Sublessee's or Assignee's financial strength, reputation, personnel, and length
of sublease or assignment shall be important factors in Lessor's approval.  The
foregoing shall not be construed to prohibit or to require Lessor's consent to
(A) a sale of Lessee's stock in a public offering, or (B) a merger of Lessee
with another entity so long as the surviving entity has a net worth immediately
after such merger at least equal to the greater of (i) Lessee's net worth as of
the Commencement Date, and (ii) Lessee's net worth immediately prior to such
merger.  If Lessor gives its approval to any sublease or assignment, Lessor
shall be entitled to (1) 50% of any excess between Lessee's rental per square
foot under the lease and the rental per square foot under the sublease or
assignment, and (2) 50% of the Net Consideration (as hereinafter defined)
received by Lessee in respect of such sublease or assignment or otherwise from
such sublessee or assignee.  For purposes hereof, "Net Consideration" means all
sums paid by the sublessee or assignee in consideration of such assignment minus
all customary and reasonable closing expenses (including, without limitation,
customary and reasonable legal and brokerage expenses) incurred in connection
with such sublease or assignment.  "Net Consideration" shall include any sums
paid for the purchase or rental of any of Lessee's property, less, in the case
of a sale thereof, the then net fair market value thereof.  The foregoing is in
consideration of additional management performed or to be performed by Lessor
under such sublease or assignment.

In addition to the foregoing, Lessor may charge Lessee for Lessee's reasonable
attorney's fees incurred in connection with the review, drafting, negotiating,
consultation and approval of any sublease, assignment, pledge or mortgage of the
Lease.  Violation of this lease by sublessees or assignees shall be deemed a
violation by Lessee.  Approval by Lessor of any sublease or assignment shall not
release Lessee from any obligation under this lease and shall not constitute
approval for subsequent subletting or assignment.  Sublessees or assignees shall
be liable for all of Lessee's obligations under this lease unless otherwise
specified in writing.  Upon default by Lessee, any Sublessee shall pay all
sublease rentals and other sums due Lessor, direct to Lessor, to be credited
against sums owed to Lessor by Lessee under this lease.  Unless otherwise agreed
in writing, no sublease or assignment shall be valid unless (1) a copy of this
lease is attached thereto, (2) the sublessee or assignee agrees in writing to be
liable for all of Lessee's obligations under this lease, and (3) Lessor's
written approval is attached to the sublease or assignment.

16.1 Destruction by Fire or Other Casualty.

(a)  Total destruction, rent abatement, and restoration. If Lessee's office
space is totally damaged by fire or other casualty so that it cannot reasonably
be used by Lessee and if this lease is not terminated as provided in
subparagraph (d) below, there shall be a total abatement of Lessee's rent and
Lessee's obligation to pay office building operating expenses until Lessee's
office space is restored by Lessor and Lessee.

(b)  Partial destruction, rent abatement, and restoration.  If Lessee's office
space is partially destroyed or damaged by fire or other hazard so that it can
be only partially used by Lessee for the purposes allowed in this lease and if
this lease is not terminated as provided in subparagraph (d) below, there shall
be a partial abatement of Lessee's rent and Lessee's obligation to pay office
building operating expenses which fairly and reasonably corresponds to the time
and extent to which Lessee's office space cannot reasonably be used by Lessee.

(c)  Restoration.  Lessor's obligation to restore shall be limited to the
condition of the Leased Premises existing prior to the casualty. Subject to the
provisions of paragraph (d) below, Lessor shall proceed with diligence to
restore. During restoration, Lessee shall continue business to the extent
commercially practical in Lessee's reasonable judgment.

(d)  Lease termination.  If Lessee's office space or the office center is so
badly damaged that restoration and repairs cannot be completed within 6 months
after the fire or casualty, or if Lessor's mortgagee will not make insurance
proceeds available for restoration, then this lease may be terminated as of the
date of the destruction by either Lessor or Lessee by serving written notice
upon the other. Termination notice must be delivered within 30 days after the
casualty.

                                    Page 11
<PAGE>

17.1 Condemnation.

If the Leased Premises or any material portion thereof, including any portion of
the parking lot is taken by condemnation and if the Leased Premises is thereby
reasonably rendered unusable for Lessee's business use and activities, this
lease shall automatically terminate as of the date title vests in the condemning
authority pursuant to such taking or acquisition; and Lessor and Lessee shall be
relieved of all further obligations under this lease.  Lessor shall be entitled
to recover from the condemning authority the full amount of Lessor's interest in
this lease and in the property which is taken in condemnation.  Lessee shall be
allowed to recover from the condemning authority, at Lessee's own expense, the
value of  Lessee's non-removable trade fixtures, if any, which are taken in
condemnation and Lessee's moving expenses to the extent that such award does not
reduce the award payable to Lessor; but not otherwise.  Lessee shall be
responsible for Lessee's own attorney's fees and for proving its own damages.

18.1 Default by Lessor.

Lessee shall be entitled to recover actual damages and/or pursue any other
remedy that may be available at law, in equity, or otherwise (other than
termination of the Lease) if (1) Lessor fails to pay any sum due and owing to
Lessee within 10 days after written demand from Lessee, or (2) Lessor fails to
perform on any other obligation for 10 days after Lessee's written demand for
performance.  However, Lessor shall not be in default if Lessor promptly
commences to cure such noncompliance and diligently proceeds in good faith to
cure same after receiving written notice of such default. If Lessor fails to
perform any covenant, term or condition of this lease that Lessor is obligated
to perform and, as a consequence of such nonperformance, Lessee shall recover a
money judgment against Lessor, such judgment shall be satisfied only out of
Lessor's equity in the property.  Lessor shall have no liability whatsoever for
any deficiency, and no other property or assets of Lessor shall be subject to
levy, execution or other enforcement procedures as a result of such judgment.
Without limitation upon the foregoing, in the event of a Lessor default, Lessee
may, after the giving of all required notices and the expiration of all
applicable cure periods, take any reasonable action to cure Lessor's default for
the account of Lessor, and any amount paid or expense incurred by Lessee in the
performance of any such matter for the account of Lessor shall be immediately
reimbursed by Lessor to Lessee upon Lessor's receipt of a demand therefor.

19.1 Default by Lessee.

If Lessee defaults, Lessor shall have any or all remedies set forth below.

(a)  Definition of default.  The occurrence of any of the following shall
constitute a default by Lessee: (1) failure to pay rent or any other sum due by
Lessee under this lease within 10 days after written demand therefor by Lessor;
(2) failure to vacate on or before the last day of the lease term, renewal term,
or extension period; (3) failure to pay rent in advance on a daily basis in the
event of unlawful holdover by Lessee; (4) unauthorized early move-out or notice
of same as set forth below; (5) acquisition of Lessee's interest in the lease by
a third party by judicial or non-judicial process; or (6) failure to comply with
any other provision of the lease (including rules) if such failure to comply is
not cured within ten (10) days after delivery of written notice by Lessor to
Lessee. However, Lessee shall not be in default under subclause (6) above if
Lessee promptly commences to cure such noncompliance within the ten (10) day
period and diligently proceeds in good faith to cure within a reasonable period
of time.

(b)  Acceleration after notice of rental delinquency.  If Lessee is in default
for nonpayment of rent or other sums due and if Lessee fails to pay same in full
within 30 days after Lessor delivers to Lessee or to Lessee's office space a
written notice of Lessor's intent to accelerate, then all rent for the remainder
of the lease term shall be accelerated, due, and delinquent at the end of such
30 day notice period without further demand or notice. Such acceleration rights
are in consideration of the rentals for the entire term being payable in monthly
installments rather than in one lump sum at the beginning of the lease term. If
Lessee has already vacated the Leased Premises, notice of acceleration may be
delivered to Lessee pursuant to paragraph 29.1. Liability for additional rents
accruing in the future (over and above any base rents) shall not be waived by
such acceleration.

(c)  Acceleration upon early move-out.  If Lessee is lawfully evicted, or if
Lessee moves out or gives written notice (in person or by an authorized employee
or agent) of intent to move-out prior to the end of the lease term without the
rent being paid in full for the entire remainder of the lease term or renewal or
extension period or without prior written consent of Lessor, all remaining rents
for the remainder of the lease term shall be accelerated immediately and
automatically, without demand or notice. Such accelerated rents shall be due and
delinquent without notice before or after such acceleration. Such acceleration
shall occur even if the rent for the current month has been paid in full.

(d)  Termination of possession.  If Lessee is in default as defined in
subparagraph (a) above and if Lessee remains in default for

                                    Page 12
<PAGE>

3 days after Lessor gives notice of such default to Lessee, or if Lessee
abandons the Leased Premises, Lessor may (with or without demand for
performance) terminate Lessee's right of possession by giving one day's written
notice to vacate; and Lessor shall be entitled to immediate possession without
termination of Lessee's obligations under the lease. Lessor's repossession shall
not be considered an election to terminate this lease unless written notice of
such intention to terminate is given to Lessee by Lessor. Repossession may be by
voluntary agreement or by eviction lawsuit. Commencement of an eviction lawsuit
shall not preclude other Lessor remedies under this lease or other laws.

(e)  Reletting costs.  If Lessee is in default under this lease and if Lessor
terminates Lessee's right of possession without terminating this lease and
Lessee's space is released, Lessee shall pay upon Lessor's demand the following:
(1) all reasonable costs of reletting including reasonable leasing commissions,
rent concessions (whether in the form of assuming or buying out lease remainders
elsewhere, free rent for a period of time, or reduced rental rates), utilities
during the vacancy, advertising costs, administrative overhead, and all costs of
repair, remodeling, or redecorating for replacement tenants in Lessee's office
space, (2) all rent and other indebtedness due from Lessee to Lessor through the
date of termination of Lessee's right of possession, and (3) all rent and other
sums required to be paid by Lessee during the remainder of the entire lease
term, subject to the acceleration paragraphs above.

(f)  Mitigation by Lessor.  Upon eviction or voluntary vacation of the Leased
Premises by Lessee without the lease being terminated by Lessor, or upon the
acceleration of the rental due hereunder, Lessor shall make reasonable efforts
to relet the Leased Premises . After deduction of reasonable expenses incurred
by Lessor, Lessee shall receive credit for any rentals received by Lessor
through reletting the Leased Premises during the remainder of the lease term or
renewal or extension period. Such deductible expenses may include real estate
commissions, attorney's fees, and all other expenses in connection with
reletting. Lawsuit to collect amounts due by Lessee under this lease may be
brought from time to time on one or more occasions without the necessity of
Lessor's waiting until the expiration of the lease term. If judgment for
accelerated rents is recovered, Lessor shall give credit against such judgment
for subsequent payments made by Lessee and subsequent rentals received by Lessor
from other tenants of Lessee's office space, less lawful deductions and expenses
of reletting.

(g)  Termination of lease.  Lessor may terminate this lease (as contrasted to
termination of possession rights only) upon default by Lessee or at any time
after Lessor's lawful re-entry or repossession following default by Lessee.
Lessor's agents have authority to terminate the lease only by written notice
given pursuant to paragraph 29.1.

(h)  Damages.  In addition to other remedies, Lessor may recover actual damages
incurred.

20.1 Landlord's Lien.

In consideration of the Lessee entering into this Lease, Lessor forever waives
and expressly releases any contractual or statutory landlord's lien that the
Lessor may now or at any time have upon the personal property of Lessee at the
Leased Premises, including, without limitation, the landlord's lien provided in
Section 54.021 of the Texas Property Code.  From time to time upon request,
Lessor agrees to execute such as may be reasonably necessary to confirm the
foregoing.

21.1 Attorney's Fees, Interest, and Other Expenses.

If Lessee or Lessor is in default and if the nondefaulting party places the
lease in the hands of an attorney in order to enforce lease rights or remedies,
the nondefaulting party may recover reasonable attorney's fees from the
defaulting party even if suit has not been filed.  In any lawsuit enforcing
lease rights, the prevailing party shall be entitled to recover reasonable
attorney's fees from the nonprevailing party, plus all out-of-pocket expenses.
Trial shall be to judge only.  All delinquent sums due by Lessor or Lessee shall
bear interest at the maximum lawful rate of interest, compounded annually, from
date of default until paid, plus any late payment fees.  Late payment fees as
set forth in paragraph 3.2 shall be considered reasonable liquidated damages for
the time, trouble, inconvenience, and administrative overhead expense incurred
by Lessor in collecting late rentals, such elements of damages being uncertain
and difficult to ascertain.  Late payment fees shall not be liquidated damages
for attorney's fees or for Lessor's loss of use of such funds during the time of
delinquency.

22.1 Nonwaiver.

The acceptance of monies past due or the failure to complain of any action,
nonaction, delayed payment, or default, whether singular or repetitive, shall
not constitute a waiver of rights or obligations under the lease.  Lessor's or
Lessee's waiver of any right

                                    Page 13
<PAGE>

or any default shall not constitute waiver of other rights, violations,
defaults, or subsequent rights, violations, or defaults under this lease. No act
or omission by Lessor or Lessor's agents shall be deemed an acceptance or
surrender of the Leased Premises , and no agreement by Lessor to accept a
surrender of the Leased Premises shall be valid unless it is in writing and
signed by a duly authorized agent of Lessor.

23.1 Building Rules.

Lessor's rules for the office building are attached as Exhibit "F-2" and are
                                                       -------------
subject to reasonable change if the changes are applicable to all tenants of the
office building.  Separate parking rules are contained in Exhibit "F-1".  Lessee
                                                          -------------
agrees to provide a copy of the Office Building Rules (Exhibit "F-2") to each of
                                                       -------------
Lessee's employees and licensees.

24.1 Transfer of Ownership by Lessor.

If Lessor transfers ownership of the office building (other than as security for
a mortgage) and if Lessor has delivered to the transferee all of Lessee's
security deposits and any prepaid rents, Lessor shall be released from all
liability under the lease; and such transferee shall become liable as Lessor.
Such right to be released of liability shall accrue to subsequent owners only if
such transfer is in good faith and for consideration.

25.1 Mortgages.

(a)  Subordination.  Lessee accepts this lease subject and subordinate to any
     -------------
mortgage, deed of trust or other lien presently existing or hereafter placed
upon the Leased Premises or the Building, and to any renewals, modifications,
extensions, consolidations or replacements thereof; provided, however, that the
holder of any such mortgage, deed of trust or other lien (hereinafter
"Mortgagee") shall have the right at any time to subordinate such mortgage, deed
of trust or other lien to this lease. Notwithstanding that this lease may be (or
made to be) superior to such mortgage, deed of trust or other lien, the
provisions of such mortgage, deed of trust or other lien relative to the rights
of the Mortgagee with respect to proceeds arising from an eminent domain taking
(including a voluntary conveyance by Lessor) and/or arising from insurance
payable by reason of damage to or destruction of the Building and/or the Leased
Premises shall be prior and superior to any contrary provisions contained herein
with respect to the payment or usage thereof. Lessee agrees upon demand to
execute such further instruments subordinating this lease as Lessor may request.
Failure to deliver such subordination agreement to Lessor within seven (7) days
after a request therefor shall constitute a default hereunder.

(b)  Attornment.  If any mortgage, deed of trust or security agreement is
     ----------
enforced by the Mortgagee, the trustee, or the secured party, Lessee shall, upon
request, attorn to the Mortgagee or purchaser at such foreclosure sale, or any
person or party succeeding to the interest of Lessor as a result of such
enforcement, as the case may be, and execute instrument(s) confirming such
attornment. In the event of such enforcement and upon Lessee's attornment as
aforesaid, Lessee will automatically become the tenant of the successor to
Lessor's interest without change in the terms or provisions of this lease;
provided, however, that such successor to Lessor's interest shall not be bound
by (a) any payment of Rent for more than one month in advance (except
prepayments for security deposits, if any), or (b) any amendments or
modifications of this lease made without the prior written consent of such
successor or Mortgagee.

(c)  Nondisturbance.  In connection with any subordination and attornment
     --------------
agreements which Lessee is required to execute as set forth above, Lessee shall
be entitled to a nondisturbance agreement from such mortgagee providing that, so
long as Lessee is not in default hereunder, that Lessee's use and enjoyment of
the Premises shall not be disturbed in the event of a foreclosure or similar
action.

26.1 Surrender of Premises.

When Lessee moves out, Lessee shall surrender Lessee's office space in the same
condition as on the date of lease commencement by Lessee (as changed or improved
from time to time in accordance with this lease), less ordinary wear.  Removal
of property from the Leased Premises is subject to paragraph 14.1.  Upon
surrender, Lessee shall provide Lessor with all of Lessee's keys, access codes
and cards to the Leased Premises and the combination to all safes and vaults, if
any in the Leased Premises.

27.1 Holding Over.

If Lessee remains in possession of the Leased Premises after the expiration or
mutually-agreed termination date of the lease, without the execution by Lessor
and Lessee of a new lease or a renewal or extension of the lease, then (1)
Lessee shall be deemed

                                    Page 14
<PAGE>

to be occupying the Leased Premises as a tenant-at-sufferance on a daily basis,
subject to all obligations of the lease, (2) Lessee shall pay rent for the
entire holdover period at the rate equal to the greater of 150% of (i) the
rental rate, in effect immediately prior to such holdover, and (ii) the then
current market rental rate for space in the building, (3) Lessee shall be
subject to all other remedies of Lessor as provided in paragraph 19.1, (4)
Lessee shall indemnify Lessor and/or prospective tenants for damages, including
lost rentals, storage expenses, and attorney's fees, and (5) at Lessor's sole
option, Lessee may extend the lease term for a period of one month at the then
current rental rates for the office building, as reasonably determined by
Lessor, by hand delivering written notice to Lessee or to Lessee's office space
while Lessee is holding over. Holdover rents shall be immediately due on a daily
basis and delinquent without notice or demand; and the prior written notice and
waiting period requirements of this lease shall not be necessary in order for
Lessor to exercise remedies thereunder.

28.1 Signs and Building Name.

Except for standard suite signage and building directory listings, and as
provided in the special provisions set forth upon Exhibit "J" attached hereto,
                                                  -----------
there shall be no signs, symbols, or identifying marks on or in the building,
halls, elevators, staircases, entrances, parking areas, landscape areas, doors,
walls, or windows without prior written approval of Lessor.  If the lease term
is less than twelve (12) months, the cost of initial suite signage for Lessee's
space and initial directory strips shall be at Lessee's expense.  All signs or
lettering shall conform to the sign and lettering criteria established by
Lessor.  Unless otherwise stated in the rules, suite signage and building
directory changes shall be done exclusively by Lessor and at Lessee's expense.
Lessor may remove all unapproved signs without prior notice to Lessee and at
Lessee's expense.  Lessor may change the name of the building upon six months'
written notice to Lessee.

29.1 Notices.

Whenever written notice is required or permitted under this lease, such notice
shall be in writing and shall be either (a) hand delivered personally to the
party being notified, (b) hand delivered to or inside such party's mailing
address, or (c) delivered at such party's mailing address by certified mail,
return receipt requested, postage prepaid.  The mailing address of Lessor shall
be the address to which Lessee normally mails or delivers the monthly rent
unless Lessor notifies Lessee of a different address in writing.  The mailing
address of Lessee shall be Lessee's office space under this lease.  However, if
Lessee moves out, it shall be Lessee's last address known by Lessor.  Hand
delivered notice is required only when expressly required in the lease.  Notice
by noncertified mail is sufficient if actually received by the addressee or an
employee or agent of addressee.  The term "notice" shall be inclusive of
notices, billings, requests, and demands.

30.1 Estoppel Certificates.

From time to time, upon 10 days' prior written request from Lessor, Lessee shall
execute and deliver to Lessor the estoppel certificate attached as Exhibit "G".
                                                                   -----------
The form in Exhibit "G" may be changed as reasonably required by a prospective
            -----------
purchaser or lender, as amended by Lessee to accurately reflect the state of
facts when the estoppel certificate is executed.  If any statement in the
estoppel certificate form is contrary to the facts existing at the time of
execution of such form, Lessee may correct same before signing.  Reasonable
modifications in the form may be made as requested by a prospective lienholder
or purchaser.  The estoppel certificate may be conclusively relied upon by
Lessor and by any prospective lienholder or purchaser of the Leased Premises.
If Lessee fails to comply with the foregoing by the end of such 10-day period,
it shall be conclusively presumed that (1) this lease is in full force and
effect without any subleases or assignments and is unamended or modified except
for amendments verified by affidavit of Lessor to the prospective lienholder or
purchaser, (2) no rents, security deposits, or other charges have been prepaid,
(3) the statements contained in the estoppel certificate form (Exhibit "G") are
                                                               -----------
correct, (4) there are no uncured defaults by Lessor, (5) Lessee has no right of
offset or rescission, and (6) any prospective purchaser or lienholder may
conclusively rely on such silence or noncompliance by Lessee and may
conclusively assume no Lessor defaults within the 120 days following Lessee's
receipt of Lessor's request for an estoppel certificate.  If Lessee fails to
execute and return any estoppel certificate requested by Lessor hereunder within
the applicable ten (10) day period, Lessee shall be in default without any
further notice or cure period being required, notwithstanding any contrary
provision in this lease.

31.1 Successors.

This lease shall bind and inure to the benefit of the parties, any guarantors of
this lease, and their respective successors and assigns.

31.2 Leasing Agent Commissions.

No leasing commission shall be due by Lessor to any leasing agent unless in
writing.  Commission agreements executed by Lessor shall be binding on
subsequent building owners if the tenant of the lease in question is in
possession at the time of transfer of building

                                    Page 15
<PAGE>

ownership.

32.1 Building Operating Expense.

In addition to the monthly base rent in paragraph 2.1, Lessee shall pay
additional rent on a monthly basis, equivalent to Lessee's prorata share of
actual building operating expenses as per Exhibit "C".  Lessee's responsibility
                                          -----------
for payment of building operating costs shall be subject to the expense stop
referred to in Basic Lease Information #8.
               ---------------------------

33.1 Representations and Warranties by Lessor.

Lessor warrants that Lessor is the sole owner of the land and improvements
comprising the office building and that Lessor has full right to enter into this
lease.  Lessor's duties and warranties are limited to those expressly stated in
this lease and shall not include any implied duties or implied warranties, now
or in the future.  No representations or warranties have been made by Lessor
other than those expressly contained in this lease.

34.1 Representations and Warranties by Lessee.

Lessee warrants to Lessor that there are no delinquent taxes due and unpaid by
Lessee.  Lessee warrants that Lessee has disclosed in writing to Lessor all
lawsuits pending or threatened against Lessee.  Lessee acknowledges that Lessor
has relied on the above information furnished by Lessee to Lessor and that
Lessor would not have entered into this lease otherwise.

35.1 Place of Performance.

Unless otherwise expressly stated in this lease, all obligations under this
lease, including payment of rent and other sums due, shall be performed in the
county where the office building is located, at the address designated from time
to time by Lessor.

36.1 Miscellaneous.

This lease contains the entire agreement of the parties.  NO OTHER WRITTEN OR
ORAL PROMISES OR REPRESENTATIONS HAVE BEEN MADE, AND NONE SHALL BE BINDING.
This lease supersedes and replaces any previous lease between the parties on
Lessee's office space, including any renewals or extensions thereunder.  Except
for reasonable changes in written rules, this lease shall not be amended or
changed except by written instrument, signed by both Lessor and Lessee.
LESSOR'S AGENTS DO NOT AND WILL NOT HAVE AUTHORITY TO (1) MAKE EXCEPTIONS,
CHANGES OR AMENDMENTS TO THIS LEASE, OR FACTUAL REPRESENTATIONS NOT EXPRESSLY
CONTAINED IN THIS LEASE, (2) WAIVE ANY RIGHT, REQUIREMENT, OR PROVISION OF THIS
LEASE, OR (3) RELEASE LESSEE FROM ALL OR PART OF THIS LEASE, UNLESS SUCH ACTION
IS IN WRITING AND SIGNED BY BOTH PARTIES TO THIS LEASE.  Multiple lessees shall
be jointly and severally liable under this lease.  Notices, requests, or
agreements to, from, or with one of multiple lessees shall be deemed to be to,
from, or with all such Lessees.  Under no circumstances shall Lessor or Lessee
be considered an agent of the other.  Nonsubstantial errors in space footage
calculations shall entitle the parties to correct the rental figures in the
lease and adjust rentals previously paid to present Owner accordingly, but not
to terminate the lease.  The lease shall not be construed against either party
more or less favorably by reason of who drafted the lease or changes in the
lease.  Texas law applies.  If any date of performance or exercise of a right
ends on a Saturday, Sunday, or state holiday, such date shall be automatically
extended through the next business day.  Time is of the essence; and all
performance dates, time schedules, and conditions precedent to exercising a
right shall be strictly adhered to without delay except where otherwise
expressly provided.  If any provision of this lease is invalid under present or
future laws, the remainder of this lease shall not be affected.

37.1 Special Conditions.

Additional provisions of this lease are set forth in Exhibit "J".
                                                     -----------

38.1 Exhibit List.

The exhibits attached to this lease are listed below.  All exhibits are a part
of this lease except for those which have been lined out or which have been
shown below as omitted.

  Exhibit  "A"   Floor Plan of Lessee's Office Space (paragraph 1.1)
  Exhibit  "B"   Legal Description of Office Building (paragraph 1.1)
  Exhibit  "C"   Building Operating Expense Passthrough Calculations (paragraphs
                 2.1 and 32.1)
  Exhibit  "D"   Acknowledgment of Lease (paragraph 4.2)
  Exhibit  "E"   Work Letter (paragraph 5.1)
  Exhibit  "F-1" Parking Rules (paragraphs 9.2 and 23.1)

                                    Page 16
<PAGE>

  Exhibit  "F-2" Building Rules (paragraph 23.1)
  Exhibit  "G"   Estoppel Certificate (paragraph 30.1)
  Exhibit  "H"   Lease Guaranty (paragraph 37.1)
  Exhibit  "I"   Corporate Resolution Authorizing Lease or Guaranty (paragraphs
                 37.1 and 39.1)
  Exhibit  "J"   Special Conditions (paragraph 37.2)
  Exhibit  "J-1" Approved Plans and Specifications for Exterior Building Signage
  Exhibit  "J-2" Schematic Drawing of Must-Take Expansion Space
  Exhibit  "K"   Hazardous Substances
  Exhibit  "L"   Acknowledgment of Receipt of Agency Disclosure
  Exhibit  "M"   Renewal Option
  Exhibit  "N"   Right of First Offer
  Exhibit  "O"   Satellite Dish/Antenna

39.1 Lease Dates and Authority to Sign.

The "identification" date of this lease is the 8th day of July 1999 (the same
date as at the top of Basic Lease Information).  The "effective date" on which
this lease becomes binding is the date on which the lease has been signed by
Lessor, Lessee, and any guarantors.  The names and signatures of all parties are
shown below; and all persons signing have been duly authorized to sign.  IF
LESSEE IS A CORPORATION, A CORPORATE RESOLUTION AUTHORIZING LESSEE TO EXECUTE
THIS LEASE IS ATTACHED AS EXHIBIT "I".  Corporate seals are unnecessary under
Texas law.


<TABLE>
<CAPTION>
LESSOR                                                       LESSEE
<S>                                                          <C>
PLAZA 7000, LTD.                                             drkoop.com, Inc.
----------------------------------------------------         -----------------------------------------------
Printed name of company or firm (if applicable)              Printed name of company or firm (if applicable)

RON POLASEK                                                  SUSAN M. GEORGEN-SAAD
----------------------------------------------------         ----------------------------------------------------
Printed name of person signing                               Printed name of person signing

____________________________________________________         ____________________________________________________
Signature                                                    Signature

VICE PRESIDENT,7000MANAGEMENT, L.L.C.,
AUTHORIZED MANAGING AGENT FOR
PLAZA 7000, LTD.  CHIEF FINANCIAL OFFICER
----------------------------------------------------         ____________________________________________________
Title of person signing (if applicable)                      Title of person signing (if applicable)

____________________________________________________         ____________________________________________________
Date signed  (Please initial all pages and exhibits)         Date signed  (Please initial all pages and exhibits)
</TABLE>

                                    Page 17
<PAGE>

LEASING AGENT

THE KUCERA COMPANY
------------------------------------------------
Printed name of company or firm (if applicable)

STEVEN G. MCMILLON
------------------------------------------------
Printed name of person signing

________________________________________________
Signature

SENIOR VICE PRESIDENT
------------------------------------------------
Title of person signing (if applicable)

________________________________________________
Date signed

                                    Page 18
<PAGE>

               EXHIBIT "A":  FLOOR PLAN OF LESSEE'S OFFICE SPACE
                         (see paragraph 1.1 of lease)

The parties agree that the floor plan below is a true and correct diagram of
Lessee's office space referred to in paragraph 1.1.

                             Plaza 7000, Suite 400
                            38,373 USF / 40,629 RSF
                            -------      -------

                                    Page 19
<PAGE>

               EXHIBIT "B": LEGAL DESCRIPTION OF OFFICE BUILDING
   by lot, block, subdivision, and county or by metes and bounds description
                         (see paragraph 1.1 of lease)


Lot 1, Greystone Center III-A, a subdivision in City of Austin, Travis County,
Texas according to the map or plat thereof recorded in Volume 83, Page 203A,
Plat Records of Travis County, Texas.

                                    Page 20
<PAGE>

      EXHIBIT "C":  BUILDING OPERATING EXPENSE PASS-THROUGH CALCULATIONS
                    (see paragraphs 2.1 and 32.1 of lease)

 (a)      "ESTIMATED" PRORATA BUILDING OPERATING EXPENSES. On or before the
beginning of each calendar year, Lessor shall calculate the estimated building
operating expenses for that calendar year, according to the criteria in
subparagraph (c) below. One-twelfth of Lessee's prorata share of estimated
building operating expenses which are in excess of any expense stop shall be due
on the first of each month as additional rent.

(b)       YEAR-END ADJUSTMENT FOR OVERPAYMENT OR UNDERPAYMENT BY LESSEE BECAUSE
OF DIFFERENCES BETWEEN "ESTIMATED" AND "ACTUAL" BUILDING OPERATING EXPENSES.
Within ninety (90) days after the end of each calendar year of the lease term
and any renewal or extension periods, Lessor shall determine the actual building
operating expenses for that calendar year. If it is then determined that actual
building operating expenses were less than estimated expenses and that Lessee's
monthly payments of estimated expenses over Lessee's expense stop figure were
too much, Lessor shall promptly credit to Lessee the excess amount paid by
Lessee to be applied against monthly installments of base rent next falling due
in the direct order of maturity or in the event the lease term is then expired
and Lessee has vacated the Leased Premises, Lessor shall promptly refund to
Lessee the excess amount in cash. If it is determined that actual building
operating expenses were more than estimated expenses and that Lessee's monthly
payments of estimated expenses over Lessee's expense stop figure were
insufficient, Lessor shall invoice Lessee for the amount of Lessee's
underpayment. Payment thereof shall be due upon delivery of invoice to Lessee.
Payment may be made prior to or with the next scheduled rental payment, but not
later. The foregoing calculations and adjustments may also be made one or more
times during the calendar year, at Lessor's option.

(c)       DEFINITION OF BUILDING OPERATING EXPENSES. Building operating expenses
for each calendar year shall include the following costs and expenses for
Lessor's operation of Plaza 7000 in accordance with this Lease: all ad valorem
taxes, assessments and related government charges becoming due on the building
and on-site personal property used solely in the operation of the building in
such period; utilities; insurance premiums for fire, extended coverage,
vandalism, and liability on the building and personal property and otherwise in
connection with the building landscape expenses; janitorial expenses; window
cleaning; supplies; painting, repairs to the roof that are not capital
improvements, window replacement, and other maintenance expenses; licenses;
permits; maintenance salaries, bonuses (which salaries and bonuses are not in
excess of market salaries and bonuses then being paid in connection with
comparable suburban office buildings in Austin, Texas); and payroll taxes,
common area utilities, reasonable management office overhead and management fees
not to exceed market management fees for comparable buildings in the suburban
office market in Austin, Texas; and all other managerial, administrative and
operating expenses which are reasonably related to the operation of the building
and utilities serving same. No such category shall include more than 12 months'
worth of expenses. Building operating expenses shall also include the following
improvements if amortized over the useful life of such improvements as
reasonably determined by Landlord together with interest at 10% per annum on the
unamortized cost: (i) improvements that in Lessor's reasonable judgment will
reduce operating expenses, (ii) carpeting, floor covering, draperies, and wall
coverings for the common areas of the building due to ordinary wear and tear.
Building operating expenses shall be calculated on an accrual basis in
accordance with generally accepted accounting principles, consistently applied.
The word "building" as referred to above shall include the building, parking
areas, parking garage (if any), and common areas.

Anything in this Lease to the contrary notwithstanding, building operating
expenses shall not include: principal and interest payments on mortgages; the
cost of capital improvements (except as provided above) and depreciation or
improvements which IRS requires to be depreciated (except as provided above);
expenses of repairing damage of the type normally covered by fire, vandalism,
flood, and EC insurance; any expense paid or reimbursed from insurance proceeds;
costs of repairing damage for which Lessor is entitled to reimbursement from
others; remodeling costs for new or existing tenants; common area improvements
or personal property required by other tenants to be made, purchased, or
furnished to such tenants; utility and air conditioning or heating costs or
other expenses which are separately billed to specific tenants; franchise and
income taxes of Lessor; leasing commissions; expenses of advertising and
marketing vacant space in the building; legal fees; structural repairs to roof,
foundation, and walls; asbestos removal; and installation of sprinklers, fire
alarms, and smoke detector systems and costs of Lessor's general corporate
overhead, and costs of any extraordinary services provided to other tenants of
the building but not to Lessee.

If utilities and taxes included in "Building Operating Expense" are not payable,
billed or otherwise due so as to allow an accurate calculation of said factors
annually, then Lessor, in its reasonable discretion, may estimate and prorate
said expenses on an annual basis, and said factors shall be properly adjusted by
Lessor when they actually become due and payable.  Otherwise, expenses must be
supported by invoices and actually paid.

(d)  DEFINITION OF PRORATA SHARE. Lessee's prorata share of estimated and
actual building operating expenses is the

                                    Page 21
<PAGE>

percentage result of dividing "Lessee's rentable area" (which is set forth in
Basic Lease Information #4) by the total rentable area in the entire building.
--------------------------

(e)       DELAY IN IMPLEMENTATION. At Lessor's option, adjustments for the then
current year may be delayed. Lessor's delay in implementing such adjustments
shall not waive Lessor's right thereto, and the most recent monthly rental
figures shall continue to be paid during such delay. If Lessor delays in timely
calculating adjustments, such adjustments shall be retroactive to the respective
date on which Lessor had a right to make such adjustment; and such delayed rent
adjustments shall become due upon written notice to Lessee.

(f)       EXAMINATION OF RECORDS. Upon reasonable notice to Lessor in writing,
Lessee may examine or audit Lessor's accounting records for building operating
expenses for the year immediately preceding and other data used in calculating
additional rents or rent adjustments. Examination or audit of building operating
expenses for a particular year may be conducted no later than 120 days after
Lessee's receipt of a reconciliation notice or statement of building operating
expenses for that year. If not examined or audited within the 120 day period,
such reconciliation shall be deemed as accepted and agreed to by all parties.

                                    Page 22
<PAGE>

                     EXHIBIT "D": ACKNOWLEDGEMENT OF LEASE
                           (To be signed at move-in)

The undersigned parties acknowledge that the lease described below is in full
force and effect and that Lessee has taken possession of the space.

     Date of lease: July 8, 1999
                   -------------
     Lessor: Plaza 7000, Ltd.
             -------------------------------------------------------------------
     Lessee: drkoop.com, Inc.
             -------------------------------------------------------------------
     Guarantor, if any (not Lessee's name):                N/A
                                            ------------------------------------
     Building name: Plaza 7000
                    ------------------------------------------------------------
     Suite No.:     400
               -----------------------------------------------------------------
     Building address:  7000 N. MoPac
                      ----------------------------------------------------------
     City/County/State/Zip:  Austin / Travis / Texas / 78731
                           -----------------------------------------------------
     Legal description of property:    See Exhibit "B" of Lease
                                   ---------------------------------------------
     Rentable Area:  40,629  Square Feet
                   ----------

The commencement date, annual anniversary date, and ending date of the initial
lease term as defined in paragraph 4.1 of above lease are as follows:

     Commencement date (month, day, year __________________________________
     Annual Anniversary date (month, day):______________________________________
     Ending date (month, day, year):____________________________________________

The parties acknowledge that the lease has not been amended or modified and that
this acknowledgment may be filed of record with the Texas Secretary of State or
the county where the building is located in order to record (1) Lessee's
possession rights to the Leased Premises, and (2) Lessor's contractual landlord
lien rights over all personal property therein and any security deposit posted
by Lessee. The entire lease is hereby affirmed and incorporated herein. The
lease will cease to be an encumbrance to Lessor's title if Lessor files an
affidavit of record, stating that Lessee no longer occupies the premises and
that Lessee's right of possession has been lawfully terminated.


LESSOR                                              LESSEE
(To be signed at move-in)                           (To be signed at move-in)

PLAZA 7000, LTD.                                    drkoop.com, Inc.
-------------------------------------------------   ----------------------------
Printed name of company or firm (if applicable)     Printed name of company or
                                                    firm (if applicable)

RON POLASEK                                         SUSAN M. GEORGEN-SAAD
-------------------------------------------------   ----------------------------
Printed name of person signing                      Printed name of person
                                                    signing

_________________________________________________   ____________________________
Signature                                           Signature

VICE PRESIDENT, 7000 MANAGEMENT, L.L.C.
AUTHORIZED MANAGING AGENT FOR
PLAZA 7000, LTD.                                    CHIEF FINANCIAL OFFICER
-------------------------------------------------   ----------------------------
Title of person signing (if applicable)             Title of person signing (if
                                                    applicable)


_________________________________________________   ____________________________
Date signed                                         Date signed

                                    Page 23
<PAGE>

STATE OF TEXAS
COUNTY OF _______________________

This instrument was acknowledged before me on _________________________________
by ____________________________________________ on behalf of the above stated
LESSOR and in the above stated capacity.

                         _______________________________________________________

                         Notary Public for the State of Texas
                         Printed name of notary_________________________________
                         My commission expires__________________________________

STATE OF TEXAS (S)
                    (S)
COUNTY OF TRAVIS    (S)

This instrument was acknowledged before me on __________________________________
by _____________________________________________ on behalf of the above stated
LESSEE and in the above stated capacity.

                         _______________________________________________________
                         Notary Public for the State of Texas
                         Printed name of notary_________________________________
                         My commission expires__________________________________

                                    Page 24
<PAGE>

                           EXHIBIT "E": Work Letter
                         (see paragraph 5.1 of lease)


Lessor: Plaza 7000, Ltd.
Lessee: drkoop.com
Date of Lease July 8, 1999
Suite Number  400
Building Name/Address  Plaza 7000/7000 N. MoPac, Austin, Texas 78731


1.   Interior Improvements.
     ----------------------

     Reference herein to "Interior Improvements" shall include all work to be
                          ---------------------
done in Lessee's Office Space and the Must-Take Expansion Space referenced upon
Exhibit "J" attached to the Lease pursuant to the Interior Improvements Plans
(defined in paragraph 2 below), including, but not limited to, partitioning,
doors, ceilings, floor coverings, wall finishes (including paint, wallpaper,
fabric and all other coverings), electrical (including lighting, light
switching, outlets, etc.), plumbing, heating, ventilating and air conditioning,
fire protection, cabinets, and other millwork, and any other improvements
required by Lessee which are not part of the "Base Building Condition" (as
hereinafter defined).  Lessor and Lessee hereby agree that unless otherwise
agreed to, the design architect for the Interior Improvements will be STG (the
"Interior Design Architect") and the construction manager for the construction
 -------------------------
of the Interior Improvements will be MoPac Construction Management, Inc. (the
"Construction Manager").  Subject to Lessor's approval (which may not be
 --------------------
unreasonably withheld), Lessee shall select the general contractor for the
construction of the Interior Improvements (the "Contractor").  Lessor shall bid
                                                ----------
out the Interior Improvements to one or more general contractors selected by
Lessee and approved by Lessor, such approval not to be unreasonably withheld.
Lessee will pay a $5,000.00 construction supervision fee to the Construction
Manager, payable periodically against the Construction Manager's invoice, on a
percentage of completion basis. Lessee will not be obligated to pay any other
construction management fee to Lessor or to any other party, unless otherwise
agreed to by Lessee.

     As used herein, "Base Building Condition" shall mean the building and all
improvements included in the base building plans kept in Lessor's office, a copy
of which may be reviewed by Lessee and Lessee's consultants and contractors
prior to the execution of this lease and periodically thereafter upon reasonable
advance notice.

2.   Interior Improvements Plans.
     ----------------------------

     Immediately after execution of the Lease, Lessee shall meet with
representatives of the Interior Design Architect for the purpose of promptly
preparing a space plan and selecting materials and finishes for the layout and
construction of improvements in the Leased Premises.  After the preparation of
the space plan and after Lessee's written approval thereof, the Interior Design
Architect shall prepare final working drawings and specifications for the
Interior Improvements based on the space plan and submit the same to Lessee for
Lessee's approval.  Such final working drawings and specifications are referred
to herein as the "Interior Improvements Plans".  A copy of the space plan and
                  ---------------------------
the Interior Improvements Plans, and each revised version thereof, shall also be
submitted to Lessor for Lessor's reasonable approval simultaneously with
submission to Lessee.  Lessee and Lessor shall promptly review each version of
the space plan and the Interior Improvements Plans and deliver any comments to
the Interior Design Architect expeditiously, and in no event later than five (5)
days after receipt of the same, so that the Interior Improvements Plans are
finally approved by Lessor and Lessee within thirty (30) days after the date of
execution of the Lease to which this Exhibit "E" is attached.  After approval of
                                     -----------
the Interior Improvements Plans by Lessor and Lessee, the same shall be
submitted to the appropriate governmental body by the Interior Design Architect
for plan checking and issuance of a building permit.  The Interior Design
Architect, with Lessee's cooperation, shall cause to be made to the Interior
Improvements Plans any changes necessary to obtain the building permit. Lessor's
approval of the Interior Improvements Plans shall create or impose no liability
or responsibility on Lessor for their completeness, design sufficiency or
compliance with applicable laws, rules or regulations of governmental agencies
or authorities.  Lessee shall work together with the Interior Design Architect,
Lessor and the Contractor diligently to finally approve the Interior
Improvements Plans and the final pricing for the construction of the Interior
Improvements not later than thirty (30) days after the date of execution of the
Lease to which this Exhibit "E" is attached.
                    -----------

                                    Page 25
<PAGE>

3.   Final Pricing and Drawing Schedule.
     -----------------------------------

     Concurrently with the plan checking, Lessor shall have the construction of
the Interior Improvements bid by one or more contractors as provided in
Paragraph 1 of this Exhibit "E" and shall deliver copies of such bids to Lessee
                    -----------
immediately upon receipt thereof for Lessee's approval, taking into account any
modifications which may be required to reflect changes in Lessee Improvement
Plans required by the city or county in which the Leased Premises are located.
All bids shall be first opened together in the presence of representatives of
Lessor and Lessee. Within five (5) days after the opening of all bids, Lessee
shall select the Contractor by written notice to Lessor. After final approval of
the Interior Improvement Plans, no further changes may be made thereto without
the prior written approval from both Lessor and Lessee, and then only after
agreement by Lessee to pay any excess costs resulting from the design and/or
construction of such changes.

4.   Construction of Interior Improvements.
     ---------------------------------------

     After the Interior Improvement Plans have been prepared and approved, the
final pricing has been approved, the Contractor has been selected and a building
permit for the Interior Improvements has been issued, the Contractor shall begin
construction and installation of the Interior Improvements in accordance with
Interior Improvement Plans. The construction manager shall only be responsible
for exercising reasonable efforts in assisting with the coordination of the
prosecution of the work to facilitate Lessee's construction schedule and for
representing the Lessor's interests in connection therewith but shall not be
responsible for securing completion, obtaining substantial completion, obtaining
a certificate of occupancy for Lessee's office space or for meeting any
deadlines, it being understood and agreed that Lessee's selected Contractor
shall be responsible for such matters. Notwithstanding the foregoing, however,
Lessor agrees to place any penalty, liquidated damages or late clauses in the
construction contract with Lessee's selected contractor, for Lessee's benefit,
provided the same are agreeable to Lessee's selected Contractor and Lessee. The
cost of such work shall be paid as provided in Section 5 below. Lessor shall not
be liable for any direct or indirect damages as a result of delays in
construction beyond Lessor's reasonable control or arising as a result of acts
of God or delays by Lessee or Lessee's agents or employees. Lessee and Lessor
agree that time is of the essence in the completion of the Interior
Improvements.

5.   Payment for the Interior Improvements.
     --------------------------------------

     a.  Except as may be otherwise provided in this work letter, Lessee shall
be responsible for the entire cost of the design, construction, and permitting
of the Interior Improvements.  In order to defray a portion of the cost of the
Interior Improvements, however, Lessor hereby grants to Lessee an "Interior
                                                                   --------
Improvements Allowance" in the amount of Twenty and No/100 Dollars ($20.00) per
----------------------
rentable square foot contained within the primary space (approximately 40,629
r.s.f.) and Twenty and No/100 Dollars ($20.00) per rentable square foot
contained within the Must-Take Expansion Space (approximately 40,629 r.s.f.).
The Interior Improvements Allowance shall be used only for:

          (1)  Payment of the cost of preparing the Interior Improvements Plans,
     including mechanical, electrical, plumbing and structural drawings, and of
     all other aspects necessary to complete the Interior Improvements Plans;

          (2)  Payment of plan check, permit, license and construction
     management fees relating to construction of the Interior Improvements.

          (3)  Construction of the Interior Improvements above and beyond Base
     Building Condition, including, but not limited to, the following:

                    (a)  Installation within the Leased Premises of all
          partitioning, doors, cabinets, floor coverings, ceiling, wall
          coverings and painting, millwork, and similar items;

                    (b)  All electrical wiring, lighting fixtures, outlets and
          switches, cabling and other electrical work to be installed within the
          Leased Premises;

                                    Page 26
<PAGE>

                    (c)  The furnishing and installation of all duct work,
          terminal boxes, diffusers, and accessories required for the completion
          of the heating, ventilation and air conditioning systems within the
          Leased Premises;

                    (d)  Any additional Lessee requirements, including, but not
          limited to, odor control, special heating, ventilation and air
          conditioning, noise or vibration control, or other special systems;

                    (e)  All fire and life safety control systems such as fire
          walls, halon, fire alarms, including piping, wiring and accessories
          installed within the Leased Premises;

                    (f)  All plumbing, fixtures, pipes and accessories to be
          installed within the Leased Premises;

                    (g)  Testing and inspection costs; and

                    (h)  Contractors' fees, including but not limited to any
          fees based on general conditions, and supervisory fees.

          (4)  Payment of the construction management fee.

          (5)  All other reasonable costs to be expended by Lessor or Lessee in
     the construction of the Interior Improvements in accordance with the
     Interior Improvements Plans.

     b.  The cost of each item referenced in Paragraph 5 a, above shall be
charged against the Interior Improvement Allowance. In the event that the cost
of installing the Interior Improvements, as established by Lessor's final
pricing schedule, shall exceed the Interior Improvements Allowance, or if any of
the Interior Improvements do not qualify for payment out of the Interior
Improvement Allowance as provided in Paragraph 5 a, above, the excess (the
"Excess") shall be paid by Lessee to Lessor within ten (10) days after Lessee's
 ------
receipt of Lessor's invoice for such Excess.  If upon substantial completion of
the Interior Improvements there remains any unused portion of the Interior
Improvement Allowance, then such unused portion may be applied towards
additional improvements to Lessee's Office Space or Must-Take Expansion Space
which benefit the space and which are agreed upon by Lessor and Lessee.

     c.  In the event that, after the Interior Improvement Plans have been
prepared and the final pricing therefor has been agreed to between Lessor and
Lessee, Lessee shall require any changes or substitutions to the Interior
Improvements Plans, any additional costs related thereto shall be paid by Lessee
on or before five (5) days from Lessee's actual receipt of Lessor's invoice for
such additional costs; provided, however, that the aggregate amount outstanding
at any one time may not exceed $25,000.00. In the event the aggregate amount of
all unpaid change orders exceeds $25,000.00 at any time, Lessee shall thereafter
be required to pay Lessor in advance for such change orders until such time as
the aggregate amount outstanding drops below the $25,000.00 threshold.

     d.  No unused portion of the Interior Improvement Allowance shall be
refunded to Lessee or available to Lessee as a credit against any obligations of
Lessee under the Lease.

     e.  No portion of the Interior Improvements Allowance will be disbursed by
Lessor until such time as the Interior Improvements Plans have been finalized
and agreed to by Lessor and Lessee and the final pricing for the construction
and installation of the Interior Improvements has been agreed to by Lessor and
Lessee.

     f.  The Interior Improvements Allowance is calculated at the rate of $20.00
per square foot of the rentable square footage of the Leased Premises and the
Must-Take Expansion Space. Subject to section 5(g), Lessor will not disburse any
portion of the Interior Improvements Allowance for space which is not being
finished out. For example, if Lessee elects not to finish out 100 rentable
square feet of the Leased Premises, Lessor will not disburse the portion of the
Interior Improvements Allowance related to such space calculated as follows: 100
X $20.00 = $2,000.00. However, such allowance will be disbursed upon such space
being finished out.

                                    Page 27
<PAGE>

     g.  In addition to the foregoing, Lessor and Lessee agree to split the cost
of demolition of the fourth floor corridor per the Interior Improvement Plans.
Lessee's share of such demolition will be deducted from the Interior
Improvements Allowance.

6.   Completion of Interior Improvements.
     ------------------------------------

     The "substantial completion date" for work described herein shall occur on
          ---------------------------
the date when all of the work described in the Interior Improvements Plans is
substantially complete as evidenced by a certificate of substantial completion
issued by the Interior Design Architect and by a Certificate of Occupancy for
the Lessee's Office Space and Must-Take Expansion Space issued by the City of
Austin, or the date such work would be substantially complete but for (a)
Lessee's failure to approve any items or perform any other obligation within the
time frames set forth in or contemplated by this Work Letter; (b) Lessee's
changes in the Interior Improvements Plans after the approval by Lessee and
Lessor. The Interior Improvements shall be deemed substantially complete
notwithstanding the fact that minor details of construction, mechanical
adjustments or decorations which do not materially interfere with Lessee's use
of the Leased Premises remain to be performed (items normally referred to as
"punch list" items). Lessor and Lessee shall complete one punch list inspection
 ----------
and Lessor shall complete and/or correct such punch list items within a
reasonable period of time.

                                    Page 28
<PAGE>

                 EXHIBIT "F-1": OFFICE BUILDING PARKING RULES
                         (see paragraph 9.2 of lease)

It is the desire of Lessor to maintain and operate the parking garage and
parking areas in an orderly manner.  The following rules and regulations apply
to all tenants in the building and their agents, employees, family, licensees,
invitees, visitors, and contractors unless otherwise stated.  Lessor reserves
the right to rescind these rules, make reasonable changes, or make other
reasonable rules and regulations for the safety, care, and cleanliness of the
parking garage, if applicable, and parking areas and for the preservation of
good order.

1.   TRAFFIC SIGNS. All persons parking in the parking areas and parking garage
shall observe posted signs and markings regarding speed, stop signs, traffic
lanes, reserved parking, no parking, parking stripes, etc.

2.   LESSEE EMPLOYEE AND CUSTOMER PARKING. Lessees and their employees and
customers [ X ]may OR [  ]may not park without charge.

3.   TRASH. All persons parking in the parking garage or parking areas shall
refrain from throwing trash, ashtray contents, or other debris on the garage
floor or parking areas.

4.   FLAT TIRES. All vehicle owners and all persons parking in the parking
garage or parking areas shall be responsible for promptly repairing flat tires
or other conditions of the vehicle which cause unsightliness in the reasonable
judgment of Lessor.

5.   REMOVAL OF UNAUTHORIZED VEHICLES. If vehicles are blocking driveways or
passageways or parked in violation of these rules and regulations or state
statutes, Lessor may exercise vehicle removal remedies under Article 6701g-1 and
6701g-2 upon compliance with statutory notice.

6.   SECURITY. Lessor shall use reasonable diligence in the maintenance of
existing lighting in the parking garage or parking areas.  Lessor shall have no
duty for additional lighting or any security measures in the parking areas,
including the parking garage.

7.   PARKING OF EMPLOYEE VEHICLES. Upon request by Lessor, Lessee shall furnish
Lessor a complete list of license numbers of all vehicles operated by Lessee,
Lessee's employees, sublessees, assignees, licensees, and all concessionaires.

8.   PARKING OF TRUCKS AND DELIVERY VEHICLES. Without Lessor's prior written
approval, no trailers or large trucks may be parked in the parking areas except
for temporary loading or unloading. Service and delivery vehicles may be parked
in loading zones only when necessary.

9.   TIMELY PAYMENT OF PARKING RENT. If applicable, Lessee shall be entitled to
monthly parking rights in the parking garage only upon timely payment of the
then current monthly parking rent, in advance.  Lessee may rent less than the
allowed number of spaces.  Lessee may rent more than the allowed number of
spaces if available in the reasonable judgment of Lessor.

10.  CONTROL DEVICES. Lessor reserves the right to install or utilize any
reasonable system of entry and exit control devices in the parking garage.

                                    Page 29
<PAGE>

                     EXHIBIT "F-2": OFFICE BUILDING RULES
                    (see paragraphs 9.2 and 23.1 of lease)


       LESSEE AGREES TO PROVIDE A COPY OF THESE RULES TO EVERY EMPLOYEE

It is the desire of Lessor to maintain in the building the highest standard of
dignity and good taste consistent with comfort and convenience for all tenants.
Any action or condition not meeting this high standard should be reported
directly to the building manager. Cooperation by all tenants will be sincerely
appreciated. The following rules and regulations apply to all tenants in the
building and their agents, employees, family, licensees, invitees, visitors, and
contractors unless otherwise stated. Pursuant to paragraph 23.1 of the lease,
Lessor reserves the right to rescind these rules, make reasonable modification
thereto, and make other reasonable rules and regulations for the safety, care,
and cleanliness of the building and for the preservation of good order.

1.   DELIVERIES AND MOVEMENT OF FURNITURE. Movement into or out of the building
of furniture, equipment shall be restricted to hours, stairways, and elevators
designated by Lessor. Unless Lessor notifies Lessee otherwise, only the freight
elevator may be used for such purposes, and such elevator may be used only
during regular business hours without prior approval of Lessor. All such
movement and delivery shall be under the supervision of the building manager and
carried out in a manner agreed between Lessee and the building manager, by
prearrangement. Prearrangement shall include time, method, routing, and any
limitations imposed for reasons of safety or nondisturbance of others. The hold
harmless and indemnification provisions of paragraph 12.3 shall apply to the
foregoing. Lessor may require that movement of furniture or equipment which
interferes with normal building traffic shall be made at hours other than normal
business hours.

2.   OBSTRUCTION OF PASSAGEWAYS.  None of the passageways, outside entries,
exterior doors, elevators, hallways, or stairways shall be locked or obstructed.
No rubbish, trash, litter, or materials of any nature may be emptied or thrown
into these areas. These areas may be used only for ingress and egress.

3.   DOORS AND DOORLOCKS. When Lessee's corridor doors are not in use, Lessee
shall use its best efforts to keep them closed on all floors where Lessee is a
partial tenant on the floor. No additional locks shall be placed on any doors in
Lessee's office space without written consent of Lessor. Lessee shall not
change, alter, or replace locks provided by Lessor on doors in the building,
except with written permission of the building manager. All necessary keys shall
be furnished by Lessor, and Lessor shall be entitled to have a key for every
door in Lessee's office space. Lessee shall surrender all keys upon termination
of Lessee's right of occupancy; and at such time, Lessee shall give Lessor the
combination to all vaults or combination locks remaining in Lessee's office
space after surrender by Lessee.

4.   SAFES. Safes and other heavy articles shall be carried onto the Leased
Premises only at such times and in such manner as prescribed by Lessor. Lessor
shall have the right to specify weight limitations and positioning of safes or
other heavy articles. Any damage done to the building by installation, presence,
or removal of a safe or other article owned or controlled by Lessee on the
Leased Premises, shall be paid for by Lessee.

5.   REMOVAL OF FURNITURE. Removal of furniture or equipment from Lessee's
office space shall require presentation of written authorization by an
authorized representative of Lessor. Security guards, watchmen, janitors, and
other building employees will have the right to challenge all persons leaving
the building with such items.

6.   INSTALLATION AND REPAIR WORK. Lessee shall refer all contractors,
contractors' representatives, and installation technicians who render any
service on or to Lessee's office space, to the building manager for approval and
supervision before performance of any service. This provision shall apply to all
work performed in the building, including installation of telephones, electrical
lines, and other electrical devices where such installation affects the floors,
walls, woodwork, trim, windows, ceilings, mechanical equipment, or any other
part of the building. If Lessee desires telephone or other electronic
connections, Lessee shall notify Lessor; and Lessor shall then direct
installation servicemen as to where and how wires may be introduced. Without
such directions, no such installations shall be permitted.

                                    Page 30
<PAGE>

7.   HAZARDOUS MATERIALS. Lessee shall not place or install, on the  Leased
Premises or any part of the building, any explosive, gasoline, kerosene, oil,
acids, caustics, or any other inflammable, explosive, or hazardous materials
without written consent of the building manager.  Lessee shall not operate
electric space heaters, stoves, engines, or other equipment not typical of an
office building without written consent of the building manager.

8.   ENTRY BY LESSOR. Lessor shall have the right to enter for the purposes and
in the manner set forth in paragraph 9.1 of the lease.

9.   PLUMBING. Plumbing fixtures and appliances shall be used only for the
purposes for which they were constructed. No sweeping, rubbish, rags, or other
unsuitable materials may be thrown or placed in plumbing fixtures or appliances.
The cost of any stoppage or damage resulting from negligence or improper use of
these fixtures and appliances by Lessee or Lessee's agents, employees, family,
invitees, licensees, or visitors shall be paid for by the Lessee.

10.  WINDOWS. Lessee shall not allow windows within Lessee's office space to be
opened at any time, except in emergencies.  Nothing shall be thrown out of the
windows of the building or down the stairwells or other passages.  Lessor
reserves the right to cause any or all windows of the building to be locked,
sealed, closed, or otherwise made inoperable, or to install permanent or
temporary screens thereon, and to include the cost thereof with the operating
expenses of the building.

11.  THEFT AND DAMAGES. Lessor shall not be responsible for lost or stolen
personal property, equipment, money, or jewelry from Lessee's office space or
from the public areas of the building, regardless of whether such loss occurs
when the area is locked against entry. Lessor will not be liable to Lessee, or
Lessee's employees, customers, or invitees for any damages or losses to persons
or property caused by other Lessees in the building or for damages or losses
caused by theft, burglary, assault, vandalism, or other crimes. Lessor shall not
be liable for personal injury or loss of Lessee's property from fire, flood,
water leaks, rain, hail, ice, snow, smoke, lightning, wind, explosions, or
interruption of utilities unless such injury or damage is caused by negligence
of Lessor. LESSOR STRONGLY RECOMMENDS THAT LESSEE SECURE LESSEE'S OWN INSURANCE
TO PROTECT AGAINST THE ABOVE OCCURRENCES.

12.  ANIMALS. No birds, fowl, or animals (except guide dogs for handicapped
persons) shall be brought into or kept in or about the building or common areas.

13.  BICYCLES AND OTHER VEHICLES. No bicycles, motorcycles, or similar vehicles
shall be allowed in the building. No trailers or large trucks may be parked in
the building parking areas except for temporary loading or  unloading.

14.  RESIDENTIAL USE. No sleeping, cooking (except in microwave ovens), clothes
cleaning, or laundering is permitted on the Leased Premises without written
consent of Lessor.

15.  INTOXICATION. Lessor reserves the right to exclude or expel from the
building any person who in the reasonable judgment of Lessor, is intoxicated or
under the influence of liquor or drugs, or who shall in any manner do any act in
violation of any rules of the building.

16.  DISTURBANCES. Lessee shall not obstruct, disturb, or interfere with the
rights of other Lessees or occupants or in any way injure or annoy them.  Lessee
shall not make any noises by any means which, in the reasonable judgment of
Lessor, are likely to disturb other Lessees or occupants of the building.

17.  COMPLIANCE WITH SAFETY AND SANITATION LAWS. Lessee shall comply with all
laws relating to fire, safety, and sanitation, and shall comply with any
requirements of Lessor's insurance company with respect to fire prevention,
safety standards, and sanitation.

18.  CLEANING. Lessee shall not employ any person or persons without written
consent of Lessor, for the purpose of cleaning or maintaining of the Leased
Premises.  Lessee shall cooperate with Lessor's employees, agents, and cleaning
personnel in keeping Lessee's premises neat and clean.  Any special cleaning
requested by Lessee and performed by

                                    Page 31
<PAGE>

Lessor or Lessor's employees, agents, or contractors shall be paid for by
Lessee.

19.  SOLICITING. Canvassing, soliciting, or peddling in the building is
prohibited without written permission of Lessor, and Lessee shall cooperate to
prevent same.

20.  SIGNS. No signs, fixtures, or notices of any kind may be displayed except
by written consent of Lessor. All signs shall conform to the requirements of
paragraph 28.1 of the lease.

21.  NOTICE OF PERSONAL INJURIES OR UTILITY OR MECHANICAL PROBLEMS. Lessee shall
give prompt notice to the building manager, to the best of Lessee's knowledge,
of any significant accidents involving injury to persons or property, including
plumbing, electrical, heating, air conditioning, stairwell, corridor, and
elevator problems and/or personal injury and property damage caused thereby.

22.  REQUESTS BY LESSEE. Except in emergencies, requests by Lessee shall be
attended to only after written request by Lessee to the building management.
Lessor's employees are not allowed to perform or do anything outside their
regular duties unless pursuant to special orders from Lessor. Lessee may not
contract with Lessor's employees for the performance of paid or free services to
Lessee. If, at the request of Lessee, Lessor or Lessor's agents furnish
services, goods, labor, or material to Lessee which are not required to be
furnished by Lessor under this lease, Lessee shall pay for same upon delivery of
a written statement therefor to Lessee.

23.  BUILDING ACCESS. Anyone who does not reasonably satisfy a building security
guard (if any) that he has a right to enter the building may be excluded by the
guard. Lessor shall not be liable for damages for any good faith error with
regard to admission or exclusion from the building of any person. In case of
fire, destruction, invasion, mob, riot, or other commotion, Lessor reserves the
right to prevent access to the building by closing the doors or otherwise.

24.  INTENTIONALLY DELETED

25.  LEASE PROVISIONS REGARDING LESSEE'S CONDUCT. Lessee shall comply with all
the provisions of paragraph 9.2 regarding parking and paragraph 10.1 regarding
occupancy, nuisance, and hazards.

26.  ELEVATORS. Lessor shall not be liable for damages from stoppage of
elevators for repair, service, or improvements.  Nor shall Lessor be liable for
delays of any duration in connection with elevator repair, service, or
improvements.

27.  SMOKING. This is a non-smoking building; smoking is not permitted anywhere
inside the building.

28.  ICE, SLEET, SNOW, OR WATER. Lessor shall have no duty to remove, in whole
or in part, ice, sleet, snow, or water from parking lots, walkways, sidewalks,
or stairs, regardless whether they are covered, uncovered, inside, or outside of
buildings.  At Lessor's option, Lessor may remove such ice, sleet, snow, or
water at any time, in whole or in part, with or without notice to anyone.

                                    Page 32
<PAGE>

                                                                 Page One of Two
This form is not to be executed at time of lease execution.
             ---

                       EXHIBIT "G": ESTOPPEL CERTIFICATE
                         (see paragraph 30.1 of lease)

The purpose of this certificate is to confirm the current status of matters
relating to the lease described below.  It is for the benefit of the owner or
prospective purchaser or mortgagee of the building in which the Leased Premises
are located.

1.   The undersigned is the Lessee under a lease between _____________________,
as Lessor, and ___________________________________ , as Lessee, dated
_____________________ on Leased Premises locally known as the __________________
building and located at _______________________, in _______________, Texas. A
copy of the fully executed lease and any amendments or modifications thereto are
attached. There are no other modifications or amendments to the above described
lease. The dates of any amendments or modifications are: (put "none" if
inapplicable) _________________________________________.

2.   There are no unfulfilled written or verbal promises, representations, or
warranties by Lessor.

3.   There are no subleases of the Leased Premises or any portions thereof.

4.   The lease (together with any amendments or modifications referred to above)
is in good standing and in full force and effect. Lessor is not in default.
Lessee agrees to give notice of any Lessor default to any purchaser or lender
making written requests to Lessee for same.

5.   Except for rents (if any) which may be due under the lease for the current
month, there are no rents or other charges which have been prepaid by the
undersigned Lessee to Lessor under the lease other than the following:
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________.

6.   The amount of security deposit currently posted by Lessee with Lessor is
$____________ in the form of ( ) cash or ( ) an irrevocable, unconditional
letter of credit issued by _____________________________ in favor of Lessor
which is still valid.

7.   Lessee acknowledges that the space being leased consists of __________
rentable square feet according to the lease, that the improvements to be
constructed by Lessor have been satisfactorily completed, that the lease space
has been accepted by Lessee, that Lessee now occupies the lease space, and that
the commencement date for the lease term was
_______________________________________.

8.   There are no rentals which are due and unpaid.  Rentals are fully paid (if
required by the lease) through the last day of the month in which this estoppel
certificate has been executed.

9.   There are no known offsets or credits against rentals except as expressly
provided by the terms of the lease.  There is no known right of rescission and
no known defense to Lessee's future obligations to pay the specified rentals at
the times and in accordance with the lease terms.  Lessee has not received any
concession (rental or otherwise) or similar compensation not expressed in the
lease which is presently in effect.

10.  Lessee has no options or rights of refusal regarding the Leased Premises or
additional rental space other than as set out in the lease.

                                    Page 33
<PAGE>

                                                            EXHIBIT "G" (cont'd)
                                                                 Page Two of Two

11.  Lessee has not: (a) made a general assignment for the benefit of creditors;
and (b) commenced any case, proceeding or other action seeking reorganization,
arrangement, adjustment, liquidation, dissolution, or composition of it or its
debts under any law relating to bankruptcy, insolvency, reorganization, or
relief of debtors; or (c) had any involuntary case, proceeding, or other action
commenced against it which seeks to have an order for relief entered against it,
as debtor, or seeks reorganization, arrangement, adjustment, liquidation,
dissolution, or composition of it or its debts under any law relating to
bankruptcy, insolvency, reorganization, or relief of debtors; or (d) concealed,
removed, or permitted to be concealed or removed, any part of its property, with
intent to hinder, delay, or defraud its creditors or any of them, or made or
suffered a transfer of any of its property which may be fraudulent under any
bankruptcy, fraudulent conveyance, or similar law; or made any transfer of its
property to or for the benefit of a creditor at a time when other creditors
similarly situated have not been paid; or (e) had a trustee, receiver, custodian
or other similar official appointed for or take possession of all or any part of
its property or had any court take jurisdiction of any other of its property.

12.  Lessee agrees to furnish Lessor with estoppel letters on this form within
10 days (stating the then-current facts) after written request by Lessor or
subsequent owners of the building.

13.  Lessee acknowledges that, upon 10 days' prior written request of Lessor's
mortgagee at any time after foreclosure proceedings or a deed in lieu of
foreclosure, Lessee shall attorn to the mortgage or foreclosure purchaser by
recognizing such new owner as Lessor under the lease provided that such
purchaser shall recognize the rights of tenant under the lease as long as tenant
is not in default. The agreement of Lessee to attorn shall survive any
foreclosure sale or deed in lieu of foreclosure. Lessee shall, upon 10 days'
written notice from Lessor's mortgagee anytime before or after foreclosure sale,
execute, acknowledge, and deliver to Lessor's mortgagee all instruments and
certificates that in the reasonable judgment of Lessor's mortgagee may be
necessary or proper to confirm such attornment.

14.  Lessee acknowledges that this estoppel certificate and the statements
therein may be conclusively relied upon by Lessor and by any prospective
purchaser or lien holder of the Leased Premises.

15.  The form of this estoppel certificate may vary, depending on lender or
purchaser requirements.  It is agreed that this certificate may be modified to
conform to reasonable requests by lenders or purchasers.

16.  This agreement shall be binding upon and shall inure to the benefit of the
Lessor, any present or future mortgagee, any prospective buyer or master Lessee
of the property, and their successors and assigns.


Dated this ________________ day of ___________________, 19____.


                              LESSEE____________________________________________

                              By _______________________________________________

                              Printed name of signatory_________________________

                              Title_____________________________________________

                                    Page 34
<PAGE>

                      EXHIBIT "H": OFFICE LEASE GUARANTY
                         (see paragraph 37.1 of lease)

                             INTENTIONALLY DELETED

                                    Page 35
<PAGE>

 EXHIBIT "I": CERTIFICATE OF CORPORATE RESOLUTION AUTHORIZING LEASE OR GUARANTY
                    (see paragraphs 37.1 and 39.1 of lease)

The undersigned, as secretary of the corporation named below, certifies that at
a special meeting of the board of directors of the corporation, duly called and
held on the _____ day of ________________, 19____, at which a quorum of the
directors were present and acting throughout, the following resolutions were
unanimously adopted and are still in force and effect:

RESOLVED that the president, the vice president, or the chief financial officer
of the corporation shall be authorized to execute a lease for office space on
behalf of the corporation and/or to guarantee performance of a lease for office
space, described below:

     Date of lease:                            July 8, 1999
                   -------------------------------------------------------------
     Lessor:                                   Plaza 7000, Ltd.
            --------------------------------------------------------------------
     Lessee:                                   drkoop.com, Inc.
            --------------------------------------------------------------------
     Guarantor, if any (not Lessee's name):    N/A
                                          --------------------------------------
     Building name:                            Plaza 7000
                   -------------------------------------------------------------
     Suite No.:                                400
               -----------------------------------------------------------------
     Building address:                         7000 North MoPac
                      ----------------------------------------------------------
     City/County/State/Zip:                    Austin / Travis / Texas / 78731
                           -----------------------------------------------------

RESOLVED FURTHER, that the president or vice president is authorized on behalf
of the Corporation to execute and deliver to the Lessor all instruments
reasonably necessary for the lease. Lessor is entitled to rely upon the above
resolutions until the board of directors of the corporation revokes or alters
same in written form, certified by the secretary of the corporation, and
delivers same, certified mail, return receipt requested, to the Lessor. The
corporation is duly organized and is in good standing under the laws of the
State of _________________________________, and there are no proceedings pending
to forfeit the corporation's charter or right to do business in Texas. The
undersigned further certifies that on the meeting date referred to above, the
names and respective titles of the officers of the corporation were as follows:


President
--------- ----------------------------------------------------------------------

Vice President
-------------- -----------------------------------------------------------------

Secretary
--------- ----------------------------------------------------------------------

Treasurer
--------- ----------------------------------------------------------------------

Chief Financial Officer
----------------------- --------------------------------------------------------

WITNESS MY HAND this _________ day of __________________________, 19_______


                              __________________________________________________
                              Typed name of corporation

                              __________________________________________________
                              Signature of secretary of corporation

                              __________________________________________________
                              Printed name of secretary



STATE OF TEXAS (S)

                                    Page 36
<PAGE>

                  (S)

COUNTY OF TRAVIS  (S)


     This instrument was acknowledged before me on ____________________________
by ________________________________________________ on behalf of the above
corporation and in the above stated capacity.

                          ______________________________________________________
                          Notary Public for the State of Texas
                          Printed name of notary _______________________________
                          My commission expires _______________________________

                                    Page 37
<PAGE>

                       EXHIBIT "J": Special Conditions
               (see special conditions paragraph 37.1 of lease)


Anything in the Lease (or its Exhibits, Schedules and Addenda) to the contrary
notwithstanding, the following special conditions shall apply to this lease and
shall prevail on any other provisions to the contrary.


1.   FINANCIAL STATEMENTS/CONSUMER CREDIT REPORT.  From time to time after
     execution of this Lease, Lessee shall, upon written request from Lessor,
     furnish to Lessor a copy of Lessee's most current financial statements in
     the possession of Lessee (such financial statements may be in the form of
     Lessee's most current United States Securities and Exchange Commission Form
     10-Q Quarterly Report and Form 10-K Annual Report so long as Lessee's stock
     is listed stock).  If at any time in the future Lessee is no longer a
     publicly traded company, such financial statements shall be signed and
     dated by Lessee or Lessee's agent and be current within twelve (12) months.


2.   TERMINATION RIGHT.  If Lessee desires expansion space anytime after the
     fifth year of the lease term and requests the space by giving Lessor six
     (6) months prior written notice (the "Expansion Space Notice") and Lessor
     cannot deliver the requested expansion space on or before the end of the
     six (6) month notice period, Lessee may terminate this lease with a ninety
     day written notice to Lessor and payment of unamortized leasing commissions
     and tenant finish out costs (using a 10% interest, principal balance only
     due at that time). Lessor shall give Lessee written notice on or before six
     (6) months after actual receipt of the Expansion Space Notice notifying
     Lessee whether Lessor can or cannot deliver the expansion space requested
     in the Expansion Space Notice, along with a certified lease expiration and
     option schedule to confirm such space will or will not be available.
     Anything in this Section 2 to the contrary notwithstanding, in the event
     Lessor does not give Lessee written notice on or before six (6) months
     after actual receipt of the Expansion Space Notice notifying Lessee that
     Lessor can or cannot deliver the expansion space requested in the Expansion
     Space Notice, along with a certified lease expiration and option schedule
     to confirm such space will or will not be available, Lessee may terminate
     this Lease upon written notice to Lessor. In the event Lessor gives Lessee
     proper and timely written notice that space will not be available, Lessee
     shall, as a condition to the exercise of Lessee's right of termination set
     forth in this Section 2, show Lessor a fully executed valid lease agreement
     signed by Lessee and proposed Lessor, for an amount of space approximately
     equivalent to Lessee's then current square footage plus requested expansion
     space.


3.   SIGNAGE.  Lessor shall grant Lessee prominent exterior building signage on
     the fourth floor of the building which conforms to the two (2) page
     drawings and specifications attached hereto as Exhibit "J-1".  As to the
                                                    -------------
     attachment to the signage to the exterior of the building, the two page
     drawings and specifications attached as Exhibit "J-1" provide for the
                                             -------------
     signage to be hung without drilling into the granite facia. Nevertheless,
     Lessor agrees that Lessee may mount Lessee's building signage to the
     building by drilling into the granite fascia if (i) such decision is made
     within ninety (90) days after the date of execution of this Lease (ii)
     Lessor approves the specific method of attachment, such approval not to be
     unreasonably withheld, and (iii) Lessee pays Lessor an amount sufficient to
     purchase and replace all granite panels which are drilled in connection
     with such exterior signage mounting. Lessee agrees to pay the cost of
     purchasing the granite to Lessor within thirty (30) days from Lessee giving
     notice to Lessor of intent to drill the granite.


4.   ARCHITECTURAL FEES.  Lessee shall use its own architect and (at its option)
     its own engineer.  Lessor agrees to pay Lessee's architect to perform a
     test fit up to an amount not to exceed $2,850.00, which amount shall not be
     deducted from the Interior Improvement Allowance.


5.   MUST TAKE EXPANSION SPACE.  The space described on Exhibit "J-2" attached
                                                        -------------
     to this Exhibit "J" is herein defined as the "Must-Take Expansion Space".
             -----------                           -------------------------
     The Must-Take Expansion Space is hereby stipulated to consist of 40,629
     square feet of net rentable area, in the aggregate. All of the Must-Take
     Expansion Space may be built out for Lessee at one time, along with the
     original portion of the Leased Premises, in accordance with the provisions
     of Exhibit "E" attached to this lease.  Lessee may begin to occupy and make
        -----------
     use of the Must-Take Expansion Space incrementally after the Commencement
     Date for any purpose permitted under the Lease

                                    Page 38
<PAGE>

     in its sole discretion; provided, however, that (i) one-third (1/3) of the
     Must-Take Expansion Space (13,543 r.s.f.) will be incorporated into the
     Leased Premises, and Lessee shall be required to commence the payment of
     rent on such portion thereof beginning on the fifth (5th) month after the
     Commencement Date (as such term is defined in Section 1 of the Lease) (ii)
                                                   ---------
     the second one-third (1/3) of the Must-Take Expansion Space (13,543 r.s.f.)
     will be incorporated into the Leased Premises, and Lessee shall be required
     to commence the payment of rent on such portion thereof beginning on the
     eighth (8th) month after the Commencement Date, and (iii) the final one-
     third (1/3) of the Must-Take Expansion Space (13,543 r.s.f.) will be
     incorporated into the Leased Premises, and Lessee shall be required to
     commence the payment of rent on such portion thereof beginning on the
     eleventh (11th) month after the Commencement Date. Anything in this Exhibit
                                                                         -------
     "J" or in the Lease to the contrary notwithstanding, Lessee shall not be
     ---
     required to pay base rent, additional "pass through" rent, or any other
     rent payable under the Lease on the Must Take Expansion Space until the
     dates and in the increments set forth in the immediately preceding
     sentence, notwithstanding that Lessee has begun to occupy part or all of
     the Must-Take Expansion Space prior to the applicable rent commencement
     dates. Subject to the abatement of rent as provided above, upon the
     Lessee's use on any portion of the Must-Take Expansion Space for any
     purpose whatsoever, including, without limitation, storage, such portion of
     the Must-Take Expansion Space shall become and be incorporated into the
     Leased Premises, and the term "Leased Premises", as used in this Lease,
     shall thereafter include the portion of the Must-Take Expansion Space so
     used by Lessee.

     On the applicable rent commencement date for each increment of the Must-
Take Expansion Space:

     (a)  the Leased Premises shall be deemed to include such incremental
          portion of the Must-Take Expansion Space;

     (b)  the Base Rent will automatically be increased by the amount per square
          foot amount set forth in Basic Lease Provisions #7 multiplied by the
                                   -------------------------
          rentable square footage contained in such incremental portion of the
          Must-Take Expansion Space; and

     (c)  Lessee's Prorata Share, as defined in Basic Lease Provisions #4, will
                                                -------------------------
          automatically be recalculated to equal the product of dividing the
          total square footage of the building (153,694) into the total rentable
          area of the Leased Premises (including all incremental portions of the
          Must-Take Expansion Space theretofore incorporated into the Leased
          Premises.

     The Must-Take Expansion Space shall be leased for a term which is
coterminous with the Term of the original Leased Premises. The Rent shall
escalate on the entirety of the Leased Premises (including the entirety of the
Must-Take Expansion Space) on each anniversary of the original Commencement Date
as provided Basic Lease Provisions #7 at the per square foot rental rate
            -------------------------
provided for in Basic Lease Provisions #7.
                -------------------------

     Upon the inclusion of all or any portion of the Must-Take Expansion Space
into Leased Premises, Lessor and Lessee shall execute, at the request of either,
an instrument delineating and describing such portion of the Must-Take Expansion
Space and confirming the inclusion thereof into the Leased Premises under the
Lease.

     The Must-Take Expansion Space shall not be severable from the Lease.

6.   PREMISES.  Approximately 40,629 rentable square feet located on the fourth
     floor(s) of the building.  This is based upon an add-on factor not to
     exceed 5.88% (subject to verification by Lessee's architect as provided in
     Section 1.3 of the Lease).  All measurements of usable and rentable square
     footage, must be computed in accordance with the American National Standard
     method of measuring floor are in office buildings of the Building Owners
     and Managers Association International (ANSI Z65.1-1996).

7.   ESCALATION.   Lessee will not be required to pay as additional "pass-
     through rent" Operating Expenses in 1999 in excess of $8.50 per rentable
     square foot of space in the Leased Premises, (subject to the rent abatement
     provisions of paragraph 7, above, regarding the Must Take Expansion Space),
     and in no event will Lessee be obligated to pay additional "pass-through"
     rent in excess of such amount during calendar year 1999.

                                    Page 39
<PAGE>

     Thereafter, controllable operating expenses (this is all those operating
     expenses excepting taxes, insurance and utilities) shall be capped at 107%
     of the previous year's controllable operating expenses.

8.   ACCESS/HVAC.  Lessor shall allow Lessee to have twenty-four (24) hour per
     day access to Lessee's office space and overtime HVAC.  The building hours
     are Monday through Friday, 7:00 a.m. to 7:00 p.m. and Saturday from 8:00
     a.m. to 1:00 p.m. At the sole cost and expense of Lessor, Lessor shall
     provide to Lessee the ability to access overtime HVAC by card key device
     without the assistance of Lessor or any other party. Afterhour HVAC charges
     shall be no more than $15.00 per hour per half floor (subject to adjustment
     for any increases in electrical charges by utility provider, but only to
     the extent of such increase as reasonably demonstrated by Landlord).

9.   PARKING.  Lessee's parking ratio is one (1) parking space per every 250
     square feet of rentable area within the Leased Premises.  Lessor shall
     allow Lessee to have reserved parking (within the above ratio) at a ratio
     of one (1) reserved parking space per every 2000 square feet of space
     within the Leased Premises at preferential locations in the garage at rates
     that are being charged other tenants in the project, but not to exceed
     $100.00 per space on the first level, $75.00 per space on the second level
     and/or $50.00 per space for levels three or higher during the initial term
     of this Lease. If Lessee does not lease all of Lessee's allotment of
     reserved parking spaces within (30) days after the Commencement Date (or,
     as to any allocation of reserved parking spaces attributable to any
     expansion space, within thirty (30) days after the date of occupancy of
     such expansion or additional space), Lessor shall be free to lease such
     unsubscribed reserved parking spaces to other tenants in the Building on
     month to month leases so that they can be recaptured by Lessee upon 45 days
     advance written notice.

10.  SECURITY DEPOSIT.  Lessor shall allow Lessee a period of two (2) weeks
     after full execution of this Lease to deliver the letter of credit referred
     to in Section 3.3 of the Lease.  So long as Lessee is not then in default,
     the security deposit shall be reduced to $89,700.00 when Lessee achieves a
     net profit (after tax) for any fiscal year.

11.  ADDITIONAL LESSEE TERMINATION RIGHTS.  Lessee may terminate this Lease upon
     written notice to Lessor in the event Lessor does not obtain a Certificate
     of Occupancy from the City of Austin for the building on or before October
     1, 1999. Notwithstanding the foregoing, Lessee shall not be entitled to
     terminate this lease pursuant to this paragraph after Lessee takes
     possession of Lessee's office space.  In addition, Lessee agrees to confirm
     the expiration of this provision in an estoppel certificate at any time
     after Lessee's move in.

12.  RENTAL ABATEMENT.  Anything in this Exhibit "J" or in the Lease to the
     contrary notwithstanding, (i) all base rent, additional "pass through"
     rent, and any other rent payable under the Lease for the Leased Premises
     shall be abated for one (1) month from the Commencement Date, (ii) Lessee
     shall receive a credit of $10,460.00 against the second month's base rent,
     and (iii) all base rent, additional "pass through" rent and any other rent
     payable under the Lease for each incremental portion of the Must-Take
     Expansion Space shall be abated for the periods set forth in paragraph 5 of
     this Exhibit "J", above.
          -----------

                                    Page 40
<PAGE>

                                 EXHIBIT "J-1"
                                 -------------

        APPROVED PLANS AND SPECIFICATIONS OF EXTERIOR BUILDING SIGNAGE
        --------------------------------------------------------------


                      TWO PAGE EXHIBIT FOLLOWS THIS PAGE

                                    Page 41
<PAGE>

                                 EXHIBIT "J-2"
                                 -------------

                SCHEMATIC DRAWING OF MUST-TAKE EXPANSION SPACE
                ----------------------------------------------

                                    Page 42
<PAGE>

                      EXHIBIT "K":  HAZARDOUS SUBSTANCES


     1.   Lessee's Obligations.  Lessee shall not cause or permit any Hazardous
          --------------------
Substance to be used, stored, generated, or disposed of on or in the Building or
the Leased Premises by Lessee, Lessee's agents, employees, contractors,
subcontractors, licensees, guests, subtenants or invitees.  If Hazardous
Substances are used, stored, generated or disposed of by Lessee on or in the
Building or the Leased Premises, or if the Building or the Leased Premises
becomes contaminated in any manner by Lessee or any of Lessee's agents,
employees, contractors, subcontractors, licensees, guests, subtenants or
invitees, Lessee shall indemnify, defend and hold Lessor harmless from any and
all claims, damages, fines, judgments, penalties, costs, liabilities, or losses
(including, without limitation, a decrease in value of the Building, damages
caused by loss or restriction of rentable or usable space, or any damages caused
by adverse impact on marketing of the space, and any and all sums paid for
settlement of claims, attorneys' fees, consultant and expert fees) arising
during or after the Term hereof and arising as a result of that contamination.
This indemnification includes, without limitation, any and all costs incurred
because of any investigation of the site or any cleanup, removal, or restoration
mandated by a federal, state, or local agency or political subdivision.

Without limitation of the foregoing, if Lessee or any of Lessee's agents,
employees, contractors, subcontractors, licensees, guests, subtenants or
invitees causes or permits the presence of any Hazardous Substance in the
Building or the Leased Premises which results in contamination, Lessee shall
promptly, at its sole expense, take any and all necessary actions to return the
Building and the Leased Premises to the condition existing prior to the presence
of any such Hazardous Substance in the Building or the Leased Premises.  Lessee
shall first obtain Lessor's approval for any such remedial action.

     2.   Lessor's Representations and Obligations.  Lessor hereby represents
          ----------------------------------------
and warrants to Lessee that, to the best of Lessor's current actual knowledge,
and based solely upon that certain Phase I Environmental Site Assessment
prepared by Law Engineering and Environmental Services, dated March 5, 1997,
there are no Hazardous Substances present or stored on, in or about the Building
or the Leased Premises and there is no Hazardous Substance contamination on the
Building, the Leased Premises or any portion thereof.  Lessor shall not cause or
permit any Hazardous Substance to be used, stored, generated, or disposed of on
or in the Building or the Leased Premises by Lessor or Lessor's agents,
employees, guests, invitees, contractors, or subcontractors.  If Hazardous
Substances are used, stored, generated or disposed of by Lessor or Lessor's
agents, employees, guests, invitees, contractors, or subcontractors on or in the
Building or the Leased Premises, or if the Building or the Leased Premises
becomes contaminated with Hazardous Substances in any way by Lessor or Lessor's
agents, employees, guests, invitees, contractors, or subcontractors, Lessor
shall indemnify, defend and hold Lessee harmless from any and all third party
claims, damages, fines, judgments, penalties, costs, liabilities, or losses
(including, without limitation, and any and all sums paid for settlement of
claims, attorneys' fees, consultant and expert fees) arising during or after the
Term hereof and arising as a result of Hazardous Substance contamination caused
by the use, storage, generation, or disposal of Hazardous Substances on or in
the Building or the Leased Premises by Lessor or Lessor's agents, employees,
guests, invitees, contractors, or subcontractors.

This indemnification includes, without limitation, any and all costs incurred
because of any investigation of the site or any cleanup, removal, or restoration
mandated by a federal, state, or local agency or political subdivision.

     3.   Definition of "Hazardous Substance".  As used herein, "Hazardous
          -----------------------------------
Substance" means any substance that is toxic, ignitable, reactive, or corrosive
and that is regulated by any local government, the state of Texas, or the United
States Government.  "Hazardous Substance" include any and all material or
substances that are defined as "hazardous waste," "extremely hazardous waste,"
or a "hazardous substance" pursuant to state, federal, or local government law.
"Hazardous Substance" includes but is not restricted to asbestos,
polychlorobiphenyls ("PCBs"), and petroleum.
                      ----

                                    Page 43
<PAGE>

         EXHIBIT "L":  ACKNOWLEDGMENT OF RECEIPT OF AGENCY DISCLOSURE

        Approved by the Texas Real Estate Commission for Voluntary Use

      Texas law requires all real estate licensees to give the following
     information about brokerage services to prospective buyers, tenants,
                            sellers and landlords.

________________________________________________________________________________

                     Information About Brokerage Services

________________________________________________________________________________

Before working with a real estate broker, you should know that the duties of a
broker depend on whom the broker represents.  If you are as prospective seller
or landlord (owner) or a prospective buyer or tenant (buyer), you should know
that the broker who lists the property for sale or lease is the owner's agent.
A broker who acts as a subagent represents the owner in cooperation with the
listing broker.  A broker who acts as a buyer's agent represents the buyer.  A
broker may act as an intermediary between the parties if the parties consent in
writing.  A broker can assist you in locating a property, preparing a contract
or lease, or obtaining financing without representing you.  A broker is
obligated by law to treat you honestly.


IF THE BROKER REPRESENTS THE OWNER:

The broker becomes the owner's agent by entering into an agreement with the
owner, usually through a written listing agreement, or by agreeing to act as a
subagent by accepting an offer of subagency from the listing broker.  A subagent
may work in a different real estate office.  A listing broker or subagent can
assist the buyer but does not represent the buyer and must place the interests
of the owner first.  The buyer should not tell the owner's agent anything the
buyer would not want the owner to know because an owner's agent must disclose to
the owner any material information known to the agent.


IF THE BROKER REPRESENTS THE BUYER:

The broker becomes the buyer's agent by entering into an agreement to represent
the buyer, usually through a written buyer representation agreement.  A buyer's
agent can assist the owner but does not represent the owner and must place the
interests of the buyer first.  The owner should not tell a buyer's agent
anything the owner would not want the buyer to know because a buyer's agent must
disclose to the buyer any material information known to the agent.


IF THE BROKER ACTS AS AN INTERMEDIARY:

A broker may act as an intermediary between the parties if the broker complies
with The Texas Real Estate License Act.  The broker must obtain the  written
consent of each party to the transaction to act as an intermediary.  The written
consent must state who will pay the broker and, in conspicuous bold or
underlined print, set forth the broker's obligations as an intermediary.  The
broker is required to treat each party honestly and fairly and to comply with
The Texas Real Estate License Act.  A broker who acts as an intermediary in a
transaction:

     (1)  shall treat all parties honestly;

     (2)  may not disclose that the owner will accept a price less than the
          asking price unless authorized in writing to do so by the owner;

     (3)  may not disclose that the buyer will pay a price greater than the
          price submitted in a written offer unless authorized in writing to do
          so by the buyer; and

     (4)  may not disclose any confidential information or any information that
          a party specifically instructs the broker in writing not to disclose
          unless authorized in writing to disclose the information or required
          to do so by The Texas Real Estate License Act or a court order or if
          the information materially relates to the condition of the property.

With the parties' consent, a broker acting as an intermediary between the
parties may appoint a person who is licensed under The Texas Real Estate License
Act and associated with the broker to communicate with and carry out instruction
so one party and another person who is licensed under that Act and associated
with the broker to communicate with an carry out instruction of the other party.


If you choose to have a broker represent you,

you should enter into a written agreement with the broker that clearly
establishes the broker's obligations and your obligations.  The agreement should
state how and by whom the broker will be paid.  You have the right to choose the
type of representation, if any, you wish to receive.  Your payment of a fee to a
broker does not necessarily establish that the broker represents you.  If you
have any questions regarding the duties and responsibilities of the broker, you
should resolve those questions before proceeding.

                                    Page 44
<PAGE>

________________________________________________________________________________

Real estate licensee asks that you acknowledge receipt of this information about
                      brokerage services for the licensee's records.


________________________________________________________________________________
Lessee Signature                                                         Date
________________________________________________________________________________

                                    Page 45
<PAGE>

                          EXHIBIT "M": RENEWAL OPTION

RIGHT OF RENEWAL.  At the end of the original lease term, Lessee will have the
----------------
option to renew the Lease for a period of sixty (60) months provided that Lessee
delivers to Lessor written notice of Lessee's exercise of such right at least
120 days prior to the end of the original lease term.  But Lessee shall not have
such right of renewal if Lessee is in default beyond any applicable cure period
allowed by the lease - either at the time of such notice of renewal or at the
end of the lease term.  When Lessee exercises its option 120 days or more prior
to end of the original term, Lessee will definitely be committed to lease the
space for the first renewal term, with rent being determined as set forth below.
The terms of the lease during such renewal term shall continue unchanged except
as follows:  Base rent shall be at ninety-five percent (95%) of fair market
rental rate as determined in accordance with the following paragraph for such
renewal term, with no tenant finish.

In the event Lessee exercises its right of renewal hereunder, Lessor and Lessee
shall attempt in good faith to agree upon the fair market rental for the
Premises during the renewal term within ten (10) days of the date of Lessee's
exercise of the renewal option.  If Lessee and Lessor are unable to so agree
upon the fair market rental for the renewal term within such ten (10) day
period, then Lessor or Lessee, by written notice given to the other (the
"Valuation Notice") may commence the valuation process specified below.
Notwithstanding the foregoing, Lessor and Lessee may at any time reach a good
faith agreement with respect to any matter which is the subject of the valuation
process specified below, including, but not limited to, the fair market rental
for the Premises during the renewal term.

Within three (3) business days following the delivery of a Valuation Notice,
Lessee and Lessor shall each select an appraiser or real estate broker
experienced in the valuation of commercial lease interests and other real
property interests in the Austin, Texas area and unaffiliated with either Lessor
or Lessee, and the appraisers or real estate brokers selected by Lessor and
Lessee shall together select a third appraiser or real estate broker (such
appraisers or brokers being collectively referred to as the "Valuing
Appraisers").  Each Valuing Appraiser shall determine the fair market rental of
the Premises for each year of the renewal term as of the first day of the
proposed renewal term (the "Valuation Date").  Fair market rental shall mean the
amount, determined as of the Valuation Date, which the Lessor could lease the
Premises for the length of the renewal term for general office purposes in an
arms' length transaction with a sophisticated unaffiliated third party without
time constraints.  Without limiting the Valuing Appraisers' consideration of any
particular relevant facts in making their determination, Lessee and Lessor
agree that the Valuing Appraisers shall take into consideration all information
that Lessee and Lessor deem relevant in connection with the determinations of
fair market rental.  Lessee and Lessor  shall deliver to each other and the
Valuing Appraisers  within ten (10) days of the appointment of the Valuing
Appraisers, any and all information reasonably requested by the Valuing
Appraisers with respect to the determination of fair market rental for the
Premises.

The Valuing Appraisers shall make their determinations of the fair market rental
of the Premises for each year of the renewal term as of the Valuation Date no
later than thirty (30) days after the delivery of the Valuation Notice.  If the
determinations of the fair market rental for any year in the renewal term by the
two Valuing Appraisers selected by Lessee and Lessor are identical, the fair
market rental for the Premises for such years in the renewal term shall be an
amount equal to such identical determinations. If the determinations of the fair
market rental for the Premises during any year of the renewal term by the two
Valuing Appraisers selected by Lessee and Lessor differ and the higher of such
two determinations (expressed as the aggregate amount of base rental for the
year) does not exceed the lower by an amount greater than ten percent (10%) of
the lower of such two determinations, then the "fair market rental" of the
Premises for such years during the renewal term shall be an amount equal to the
average of such two determinations for the subject year. If the determinations
of the fair market rental of the Premises for any year during the renewal term
from the Valuing Appraisers selected by Lessor and Lessee differ and the higher
of the two determinations(expressed as the aggregate amount of base rental for
the year) exceeds the lower by more than ten percent (10%) of the lower of such
two determinations, then the "fair market rental" of the Premises for such years
in the renewal term shall be an amount equal to the average of the two fair
market rental determinations of the three Valuing Appraisers closest to each
other, or, if the highest and the lowest of such three determinations are equal
distance from the middle of such three determinations, the middle fair market
rental determination.

                                    Page 46
<PAGE>

All fees and costs of the Valuing Appraisers and any other expenses associated
with the determination of fair market rental  in accordance with this Exhibit
shall be paid fifty percent (50%) by Lessor and fifty percent (50%) by Lessee.

                                    Page 47
<PAGE>

                       EXHIBIT "N": RIGHT OF FIRST OFFER
                       ---------------------------------

Provided that Lessee is not then in default under the Lease, Lessee shall have a
continuous right from time to time to lease additional office space within the
building according to the terms and conditions set forth below.


1.  RIGHT OF FIRST OFFER.  Lessor shall not renew or extend the lease term
    --------------------
(including entering into a new lease following the expiration of a primary or
renewal term) nor permit the exercise of a renewal or extension term by any
building tenant leasing on the first floor of the building without first
offering to lease any such space to Lessee; provided, however, that any building
tenant leasing more than 7,500 rentable square feet on the first floor of the
building may exercise any renewal option granted in such tenant's lease
agreement with Lessor and the space to be leased under any such renewal option
shall not be subject to Lessee's right of first offer.  The space on the first
floor or the building described in the preceding sentence that is subject to
Lessee's right of first offer is referred to hereinafter as the "Offer Space".
                                                                 -----------
Lessor shall notify Lessee in writing not less than 180 days prior to the
expiration of any primary, renewal or extension term of any tenant leasing any
portion or all of the Offer Space. Lessee shall have ten (10) business days from
receipt of such notice from Lessor to give Lessor notice of its decision to
lease the portion of the Offer Space so offered. If Lessee does not elect to
lease such space within such time period, Lessor shall be free to enter into a
renewal or extension term on such portion of the Offer Space with such tenant or
to enter into a new Lease of such space with any other tenant. The rental rate
for such additional space shall be at the prevailing market rate (determined
with respect to the building and similar office complexes in the Austin, Texas
area), which market rate shall be determined substantially in accordance with
the provisions set forth on Exhibit "M" attached hereto for the determination of
                            -----------
market rent. The lease term for such additional space shall commence on the
sooner of the date such space is available for lease or the date the premises
are ready for occupancy by Lessee, and such term shall continue for the then
unexpired current term of this Lease, whether it be the original lease term or a
renewal term, provided, however, if less than three (3) years remain in the
primary term of the Lease at the time Lessee exercises a right to lease Offer
Space, the primary term of the Lease shall be extended for an additional three
(3) years. The lease term and conditions for such additional space shall be the
same as set forth in this Lease except for commencement date and rental rates.
Lessee's rights under this Section 1 shall be continuous and shall apply as to
each availability of any portion or all of the Offer Space, notwithstanding any
prior election not to exercise its rights hereunder to lease part or all of
Offer Space.

To facilitate and effect this Section 1, Lessor agrees that each lease agreement
with any tenant of the building (other than Lessee and Ivy, Crews & Elliott,
P.C.) leasing 7,500 or less rentable square feet on the first floor of the
building shall include a subordination provision subordinating the rights of the
tenants and Lessor to the Lessee's rights set forth herein.

Anything in this Lease to the contrary notwithstanding, the provisions of
Section 1 shall not become effective and Lessee may not exercise its rights of
first offer under this Section 1 unless and until Lessee achieves the profit
level required in Section 10 of Exhibit "J" to the Lease that is necessary to
                                -----------
reduce Lessee's security deposit under the Lease.

This Right of First Offer is not applicable to the initial lease up of the
building.

2.  AMENDMENT TO LEASE.  If Lessee elects to lease space in accordance with
    ------------------
Sections 1 above, Lessor shall submit a lease amendment to Lessee within  five
(5) business days after receiving Lessee's notice of such election. Lessee shall
have five (5) business days after receipt of the amendment to execute and return
same to Lessor. If the amendment accurately reflects the provisions of this
Exhibit and is not executed by Lessee and returned to Lessor within such time
period, the right of first offer granted herein with respect (and only with
respect) to the particular space then being offered shall terminate
automatically and without further notice. The amendment shall only amend the
particular lease paragraphs or provisions which are affected.

                                    Page 48
<PAGE>

                      EXHIBIT "O": Satellite Dish/Antenna
                      -----------------------------------

Lessor agrees to allow Lessee to install and operate during the term of the
lease a single (one) communications antenna or satellite dish and appurtenant
equipment on the roof of the parking garage adjacent to the Building.  Such
antenna must conform to the specifications and drawings, and be in the location
designated by Lessor, on Exhibit "O-1" attached to this Exhibit "O".  Such
                         -------------                  -----------
antenna may not be placed on any other portion of the roof of the parking
garage, including, without limitation, any portion thereof that is exclusively
for the use of any third party or other tenant of the Building.  Such antenna
shall be further subject to all applicable laws, regulations and ordinances, the
rights of other tenants of the Building to install such equipment, and the
obligation of Lessor to maintain the general appearance of the project,
including the roof-top of the parking garage.  Lessee shall ensure that such
antenna does not interfere with any communications equipment or other equipment
of Lessor, other tenants in the Building or of other antenna licensees.  In the
event of any such interference, Lessee shall take all steps necessary to cause
such interference to cease, including, if necessary, removal of such antenna.
Lessee shall pay as additional rent for such antenna or satellite dish the sum
of Two Hundred Fifty and No/100 Dollars ($250.00) per month, and the cost of the
installation of any such antenna or satellite dish shall be borne solely by
Lessee.  Lessee shall indemnify Lessor for any liens, damage, loss, cost,
expense and liability incurred as a result of such antenna and the operation
thereof and all costs or expenses incurred by Lessor in connection with the
installation or use of such communications antenna or satellite dish.  Lessee
agrees that Lessee's antenna will be directed to the southwest and will be
pointed upward approximately 20 degrees from the horizon.  Lessor covenants that
it will not obstruct the site-line of Lessee's satellite dish with other
antennas or improvements on the parking garage roof and shall not permit the
obstruction by other tenants of the building or antenna licensees upon the
parking garage roof of the site-line of Lessee's satellite dish.

                                    Page 49
<PAGE>

                            BASIC LEASE INFORMATION

The following Basic Information is incorporated into and made a part of this
lease. Each reference in this lease to any of the Basic Lease Information shall
mean the respective information set forth below and shall be construed to
incorporate all of the terms provided under the particular lease paragraph(s)
pertaining to such information. In the event of a conflict between any Basic
Lease Information and the lease, the lease shall control.

IDENTIFICATION DATE OF LEASE: 07/08/99     [X] New   [_] Renewal [_] Expansion
                                           [_] Other

1.   Name of Building: Plaza 7000           Address: 7000 North Mopac / Austin,
                      ------------------            ---------------------------
                                                     Texas 78731
                                                    ------------

2.   Owner/Lessor:     Plaza 7000, Ltd.     Address: 7200 North Mopac #420 /
                  ----------------------            ---------------------------
                                                     Austin, Texas  78731
                                                    ---------------------
3.   Suite Number:     400
                  ----------------------

4.   Usable SF:   38,373        Add-On Factor:    5.88%     Rentable SF: 40,629
               -------------                   ---------                -------

     Total Bldg. SF: 153,694    Pro Rata Share:  26.43%
                    --------                    --------

5.   Lessee Name:  drkoop.com, Inc.
                 ---------------------------------------------------------------

     a)   Lessee is, [X] a corporation, (check one).

     b)   Lessee Address for Notice:____________________________________________

     c)   Lessee Contact Person:____________ Phone: _____________ Fax:__________

     d)   Lessee Taxpayer ID#:______________ SS#:________________ DL#/State:____

6.   Lease Term: eighty-five (85) full calendar months
                ------------
     Commencement Date:                     09/01/99  Expiration Date: 09/30/06
                                            --------                   --------
     Rent and Pass Thru Commencement Date:  09/01/99  Expiration Date: 09/30/06
                                            --------                   --------

<TABLE>
<CAPTION>
7.   Base Rent:            Term                Monthly Rent          Term Rent      Annual Rent psf of NRA
                           ----                ------------          ---------      ----------------------
     <S>        <C>                             <C>                <C>              <C>
                Month 1                         $     0.00         $      0.00              $ 0.00
                Months 2 through 13             $60,943.50         $731,322.00              $18.00
                Months 14 through 25            $62,636.38         $751,636.56              $18.50
                Months 26 through 37            $64,329.25         $771,951.00              $19.00
                Months 38 through 49            $66,022.13         $792,265.56              $19.50
                Months 50 through 61            $67,715.00         $812,580.00              $20.00
                Months 62 through 73            $69,407.88         $832,894.56              $20.50
                Months 74 through 85            $71,100.75         $853,209.00              $21.00

                Late Charge:  3% of monthly base rent.     Date assessed: Five (5) days after due date.
                             --------------------------                   ----------------------------
</TABLE>

8.   Expense Stop: $0.00 (NNN) per square foot per year
                  ------------

     a)   Estimated Operating Expenses Per Budget $ 8.50 / sq.ft./year
                                                  --------------------
     b)   Less Expense Stop                       $ 0.00 / sq.ft./year
                                                  --------------------
     c)   Estimated Initial Pass-Thru             $ 8.50 / sq.ft./year
                                                  --------------------
     d)   Estimated Monthly Pass-Thru (actual)    $28,778.88/mo
                                                  --------------------
          (Subject to annual adjustment for actual expenses)

<TABLE>
<S>                                                              <C>
9.   Parking:  Number of Reserved Spaces:    1:2000              Rate Per Space: See Special Conditions
                                         ---------------------                   ----------------------
               Number of Unreserved Spaces:  1:250               Rate Per Space  $ 0.00     / month
                                           -------------------                   ----------------------
               Customer parking changes (  ) are or ( X ) are not allowed.
</TABLE>

10.  Security Deposit: c) Irrevocable Letter of Credit: $250,000.00
                                                        -----------

     Rec'd: _________  Yes _________ No

11.  Tenant Finish Out Provisions:


                                  Page 1 of 2
<PAGE>

     a)   ____________ As Is
     b)   $20.00       /sq. ft. of net rentable area allowance
          ------------
     c)  $812,580.00 (plus allowance for must take space) total allowance
         ------------------------------------------------
         (actual amount)
     d)  Amount of overage owed by Tenant $__________ Payment Schedule:_________
     e)  Notes:_________________________________________________________________

12.  Special Conditions (Exhibit J)
     a)  Current Financials received: _____ Yes ____ No
     b)  Consumer Report received:    _____ Yes ____ No
     c)  OT HVAC charge:                X   Yes ____ No; $15.00 per hour per
                                      -----              ------
         half floor
     d)  Notes:_________________________________________________________________

13.  Guaranty Information
     This lease [_]is or [X]is not (check one) guaranteed by others. The name
     and title of each guarantor is shown below and on the signature page(s) at
     the end of this lease.

14.  Lessee Signature Requirements
     Lessee is [X]a corporation, (check one).

     Such partnership, joint venture, unincorporated association, or corporation
     is organized or chartered under the laws of the State of Delaware.
                                                              --------
     Lessee's name stated at the beginning of this lease [_]is or [X]is not
     (check one) an assumed name. If so, has an assumed name certificate name
     been received? [_]Yes or [_]No

<TABLE>
15.  Broker Information:
     <S>                                               <C>
     a)  Listing Broker Company and Agent:             The Kucera Company / Steve McMillon and Jeff Henley
                                                       ---------------------------------------------------
     b)  Leasing Co-Broker Company and Agent:          Insignia/ESG / Bart Matheney
                                                       ---------------------------------------------------
     c)  Tenant Rep letter attached:                   _______ Yes    X    No
                                                                    -----
     d)  Written agreement for renewal commission:     _______ Yes    X    No _______ %
                                                                    -----
</TABLE>

16.  This Basic Lease Information Form is a part of the above described lease.

17.  Signatures:

     LESSOR                                  LESSEE

     PLAZA 7000, LTD.                        drkoop.com, Inc.
     --------------------------------        -----------------------------------
     Printed name of company or firm         Printed name of company or firm

     RON POLASEK                             Susan M. Georgen-Saad
     --------------------------------        -----------------------------------
     Printed name of person signing          Printed name of person signing

     _______________________________         ___________________________________
     Authorized Person's Signature           Authorized Person's Signature

     VICE PRESIDENT, 7000 MANAGEMENT, L.L.C.
     AUTHORIZED MANAGING AGENT FOR
     PLAZA 7000, LTD.                        Chief Financial Officer
     --------------------------------        -----------------------------------
     Title of person signing                 Title of person signing

     ________________________________        ___________________________________
     Date signed  (must be filled in)        Date signed (must be filled in)

                                  Page 2 of 2