<PAGE>
                                                                    Exhibit 10.9

                                 LEASE CONTRACT

     This Lease Contract (the "Lease") is entered into between GREENWAY PLAZA,
LTD., a Texas limited partnership ("Landlord"), and PHYSIX, INC., a Texas
corporation, ("Tenant"), and is effective as of the "Effective Date" provided in
Paragraph 33. below.

1.  PREMISES

     A.   Landlord hereby leases to Tenant and Tenant hereby leases from
          Landlord approximately 7,433 square feet of "Rentable Area" (as
          hereinafter defined) on the sixth (6th) floor of Two Greenway Plaza
          (the "Building"), located on the land described in Exhibit "A" (the
          "Land") in Houston, Harris County, Texas.  The area leased in the
          Building is hereinafter called "Leased Premises" and is shown outlined
          and hatched on Exhibit "B".  Landlord shall have the right at any time
          and from time to time to change the Building name.  The Land, the
          Building, together with landscaping, driveways, sidewalks, service
          areas, all other improvements located on the Land, and the Building
          garage ("Parking Garage") are hereafter collectively called the
          "Project".

     B.   On each floor of the Building on which space rentable to tenants is or
          will be leased to one tenant, the Rentable Area for such floor
          ("Single Tenant Floor") shall be the entire area bounded by the
          interior of the exterior walls of the Building on such floor less the
          area contained within the Building stairs, vertical ducts, elevator
          shafts, flues, vents, stacks, and pipe shafts.  All the area on any
          Single Tenant Floor that is used for elevator lobbies, corridors,
          special stairways, restrooms, mechanical rooms, electrical rooms, and
          telephone closets, all vertical penetrations that are included for the
          special use by Tenant, columns and other structural portions of the
          Building, plus a pro rata portion of the Building's ground floor
          lobbies, mechanical rooms and other similar facilities utilized by all
          Building tenants, shall be included within the Rentable Area of the
          Single Tenant Floor.

     C.   On each floor of the Building on which space rentable to tenants ir or
          will be leased to more than one tenant ("Multi-tenant Floor"), the
          Rentable Area attributable to each such lease shall be the total of
          (1) the area bounded by the interior of the exterior wall or walls of
          the Building bounding such leased premises, the exterior of all walls
          separating such leased premises from any public corridors or other
          public areas on such floor and the center line of all walls separating
          such leased premises from other areas leased or to be leased to other
          tenants on the Multi-tenant Floor, and (2) a pro rata portion of the
          area covered by the elevator lobbies, corridors, restrooms, mechanical
          rooms, electrical rooms, telephone closets, columns and other
          structural portions of the Building situated on the Multi-tenant
          Floor, plus a pro rata portion of the Building's ground floor
<PAGE>

          lobbies, mechanical rooms and other similar facilities utilized by all
          Building tenants. The Rentable Area for the entire Building shall be
          deemed to be 212,232 square feet for the purpose of this Lease.

2.  TERM

     The term of this Lease shall commence November 1, 1996 ("Commencement
Date"), and shall expire February 28, 2004 ("Expiration Date").  In the event
the Leased Premises should not be ready for occupancy by the Commencement Date
for any reason, Landlord shall not be liable or responsible for any claims,
damages or liabilities in connection therewith or by reason thereof; and the
term of this Lease shall commence at the time that the Leased Premises are ready
for occupancy by Tenant, Landlord and Tenant, at the request of either, will
execute a declaration specifying the square feet of Rentable Area contained
within the Leased Premises, the beginning date of the term of this Lease and
such beginning date will then constitute the Commencement Date.  In such event,
rental under this Lease shall commence, subject to a rental abatement period as
provided below, on said revised Commencement Date and the stated term in this
Lease shall thereupon commence, and the Expiration Date shall be extended to
effect a full eighty-eight (88) month term.  If the Leased Premises are not
"Substantially Completed" (as hereinafter defined) by February 1, 1997 (the
"Outside Completion Date") [subject to delays due to force majeure, Tenant
delays, or delays beyond the reasonable control of Landlord]; upon written to
Landlord, Tenant shall have the one time right to terminate this Lease within
ten (10) days following the Outside Completion Date.  If the Lease is
terminated, all deposits paid to Landlord by Tenant under this Lease shall be
promptly refunded by Landlord to Tenant and neither party shall have any further
obligations or liabilities under this Lease.  "Substantial Completion", as said
term is used herein, shall mean that date, as reasonably determined by Landlord
or Landlord's architect, when all of the improvements required to be performed
by Landlord have been completed excepting completion or correction of minor
items which do not significantly impair Tenant's ability to occupy and use the
Leased Premises for the purposes intended.

3.  RENT

     As "Base Rental" for the lease and use of the Leased Premises, Tenant will
pay Landlord or Landlord's assigns, at the Building office or post office
address of Landlord or such other address as Landlord may hereafter specify in
writing, without demand and without deduction, abatement or setoff (except as
otherwise expressly provided for herein), as follows:

<TABLE>
<CAPTION>
Time Period                # of Months         Rate           Monthly Rent
-----------                -----------        ------          ------------
<S>                        <C>                 <C>            <C>
11/01/96-02/28/97               04            $00.00            $    0.00
03/01/97-08/31/00               42            $12.00            $7,433.00
09/01/00-02/28/04               42            $13.00            $8,052.42
</TABLE>

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The Base Rentals outlined above are due and payable on the first day of each
calendar month, monthly in advance, for each and every month in the term of this
Lease, in lawful money of the United States.  The Base Rental payable for
partial months occurring at the beginning or end of the Lease term shall be
prorated.  The terms "rent" or "rental" shall mean Base Rental and all other
sums to be paid to Landlord by Tenant under the provisions of this Lease.

4.   USE

     Tenant will use the Leased Premises solely for the purpose of office space
and for no other purpose without the prior written consent of Landlord.

5.   SERVICES TO BE PROVIDED BY LANDLORD

     A.   Landlord shall furnish Tenant, at Landlord's expense subject to
          Paragraph 13, the following services during the Lease term:

          (1)  Air conditioning and heating in season, at such temperatures and
               in such amounts as are considered by Landlord to be standard,
               from 8:00 a.m. until 6:00 p.m., Mondays through Fridays, and from
               8:00 a.m. to 12:00 Noon, on Saturdays, excluding Holidays, as
               defined below.  Service on Saturdays (after 12:00 Noon), Sundays
               and Holidays will be furnished only upon the request of Tenant,
               who shall bear the cost thereof.  The following days constitute
               "Holidays":  New Year's Day, Memorial Day, Independence Day,
               Labor Day, Thanksgiving Day and Christmas Day.  Such charges for
               after hours air conditioning and heating for the base building
               air handling units are currently Tenant and 33/100 Dollars
               ($10.33) per hour per air handler with a maximum charge of
               Twenty-Five and 00/100 Dollars ($25.00) per hour per floor.  If
               Tenant utilizes supplemental fan coil units, Tenant shall be
               responsible for the electric charges (as such rates are set by
               Houston Lighting & Power) and chilled water charges which are
               currently set at Twenty Cents ($.20) per ton hour.  Increases in
               the above stated charges shall be based upon actual cost
               increases plus reasonable cost of Landlord overhead.

          (2)  Hot and cold water at those points of general supply provided on
               the floor on which the Leased Premises are located.

          (3)  Janitor service in and about the Building and the Leased Premises
               five (5) days per week (excluding Holidays) and periodic window
               washing.  Tenant shall pay costs attributable to the cleaning of
               improvements within

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               the Leased Premises other than Building standard improvements.
               The term "Building standard improvements" refers to the common
               type of building materials, fixtures, and components used by
               Landlord in the ordinary build-out of premises for tenants in the
               Building.

          (4)  Building elevators for access to and egress from the Leased
               Premises twenty-four (24) hours a day, seven (7) days a week.

          (5)  Proper facilities to enable the appropriate utility company to
               furnish electricity for Building standard lighting, typewriters,
               dictating equipment, copiers, calculating machines, personal
               computers and other machines of similar low electrical
               consumption, but not including electricity required for
               electronic data processing equipment, special lighting in excess
               of Building standard, or any item of electrical equipment which
               single consumes more than 0.25 kilowatts per hour at rated
               capacity or requires a voltage other than 120 volts single phase,
               regardless of whether such special lighting or other equipment
               was paid for out of funds that Landlord may have supplied for the
               improvement of the Leased Premises, Tenant shall pay Landlord
               monthly [illegible words] separately-metered charges for any
               electricity in excess of that stated above (the cost of any such
               meter and its installation to be borne by Tenant), or if not
               separately metered, the charge for such excess electricity as
               Landlord's engineer may compute.  Upon approval by Landlord and
               Tenant of engineered drawings for the improvements to be made to
               the Leased Premises, Landlord shall give Tenant notice if any
               such separate meters are required.

          (6)  Replacement of fluorescent lamps and ballasts in Building
               standard ceiling mounted fixtures installed by Landlord and
               incandescent bulb replacement in all public areas.

     B.   Subject to the provisions of Paragraph 5.C. below, no interruption or
          malfunction of these services (including, without limitation, acts of
          God, or the actions, regardless of the ultimate validity or
          enforceability thereof, of any governmental, quasi-governmental,
          regulatory or executive authority) shall constitute an eviction or
          disturbance of Tenant's use and possession of the Leased Premises or a
          breach of any of Landlord's obligations or render Landlord liable for
          damages or entitle Tenant to be relieved from any of its obligations
          (including the obligation to pay rent).  In the event of any
          interruption or malfunction, Landlord shall use reasonable diligence
          during Landlord's normal business hours to restore service when
          restoration is within its reasonable control.

     C.   Any Landlord's failure to provide the services specified in Paragraph
          5.(a)(1), (2) for restrooms only and provided Landlord cannot provide
          alternate facilities in the

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<PAGE>

          Building,] (4) and (5) which results in all or any part of the Leased
          Premises being rendered unsafe or in any way unsuitable for use by
          Tenant in the ordinary conduct of its business is herein referred to
          as a "Constructive Eviction". If a Constructive Eviction occurs and is
          not cured within five (5) working days after receipt by Landlord of
          written notice from Tenant of the existence of such Construction
          Eviction, Tenant shall have the following rights and remedies:

          (1)  For each day or portion thereof that the Constructive Eviction
               continues after the initial five (5) day period, and provided
               that Tenant is not using such space in a reasonably normal
               manner, specifically recognizing the number of employees
               utilizing such space is not a basis for using such space in a
               reasonably normal manner, Tenant will be entitled to an equitable
               abatement of rent commensurate with that portion of the Leased
               Premises to which such Landlord's services have been interrupted,
               calculated on a per square foot basis, beginning with the
               inception of the sixth (6th) working day and terminating at the
               time the Constructive Eviction is completely cured by Landlord
               having resumed furnishing the interrupted service or having
               rendered the Leased Premises again suitable for use by Tenant for
               its intended purposes.

          (2)  If the Constructive Eviction is caused by Landlord's fault and is
               not completely cured within thirty (30) days, or, if the
               Constructive Eviction is not caused by Landlord's fault and is
               not cured within sixty (60) days, then Tenant, at its option may
               terminate this Lease and all of its obligations for the remaining
               balances of the term.  If Tenant so elects to terminate this
               Lease, it shall so notify Landlord in writing at anytime prior to
               Landlord curing the Constructive Eviction.

          (3)  Tenant's remedies for failure to provide services as set out in
               this Paragraph 5.C. are limited to those so provided in this
               Paragraph 5.C.

     D.   Should Tenant desire any additional services beyond those described in
          subparagraph 5A or rendition of any of such service outside the normal
          times they are provided by Landlord, Landlord may (at Landlord's
          option), with reasonable prior request from Tenant, furnish such
          service; and Tenant agrees to pay Landlord charges as may be agreed on
          between Landlord and Tenant, but in no event a charge less than
          Landlord's actual cost plus overhead for the additional services
          provided.  It is agreed that the cost to Landlord of such additional
          services shall be excluded from the "Project Operating Cost," as
          defined in subparagraph 13B.

6.  REPAIR AND MAINTENANCE

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     A.   Landlord will, at its own cost and expense, except as may be provided
          elsewhere herein, make necessary repairs or damage to the Building's
          corridors, lobby, structural members, and equipment used to provide
          the services referred to in subparagraph 5A unless the damage is
          caused by acts or omissions of Tenant, its agents, customers,
          employees or invitees, in which event Tenant will bear the cost of
          repairs.  Tenant will promptly give Landlord written notice of any
          damage requiring repair by Landlord.

     B.   Tenant will not injure the Leased Premises, Building or any other part
          of the Project and will maintain the Leased Premises in a clean,
          attractive condition and in good repair, except for damage to be
          repaired by Landlord, as provided above.  Upon expiration or
          termination of this Lease, Tenant will surrender the Leased Premises
          to Landlord in the same condition in which it existed at the
          Commencement Date, excepting only ordinary wear and tear, damage
          arising from any cause not required to be repaired by Tenant, and
          alterations or additions permitted to remain under subparagraph 10B.

     C.   This Paragraph 6 shall not apply in the case of damage or destruction
          by fire or other casualty which is covered by insurance maintained by
          Landlord on the Building (as to which Paragraph 7 shall apply), or
          damage resulting from an eminent domain taking (as to which Paragraph
          14 shall apply).

7.  FIRE OR OTHER CASUALTY

     A.   Tenant shall give prompt written notice to Landlord of any material
          damage caused to the Leased Premises by fire or other casualty as soon
          as reasonably possible after learning of the damage.  If the Leased
          Premises or twenty percent (20%) or more of the floor area of the
          Building are damaged or destroyed by fire or other casualty, then
          Landlord shall have the option to terminate this Lease by giving a
          notice of Lease termination to Tenant within sixty (60) days from the
          date of the damage or destruction.  In the event this Lease is
          terminated by Landlord, Landlord shall refund to Tenant the prepaid
          rend (unaccrued as of the date of damage or destruction), less any sum
          then owing Landlord by Tenant.

     B.   If Landlord has no exercised its option to terminate the Lease, the
          Lease shall continue in full force and effect, and repairs will be
          made by Landlord within a reasonable time thereafter, subject to
          delays arising from shortages of labor or material, acts of God, war
          or other conditions beyond Landlord's reasonable control.  Rent shall
          abate proportionately during Landlord's repair period to the extent
          the Leased Premises are unfit for use by Tenant in the ordinary
          conduct of its business and are not used by Tenant.  Landlord's repair
          obligation shall be limited to Fifteen & 00/100 Dollars ($15.00) per
          square foot of Rentable Area contained within the Leased Premises.
          Landlord shall not be liable to Tenant for

                                      -6-
<PAGE>

          any inconvenience or annoyance to Tenant, or injury to Tenant's
          business resulting from the damage or destruction or any subsequent
          repair work.

     C.   If Landlord does not exercise its option to terminate the Lease, as
          provided in Paragraph 7.A above, but fails to restore the Leased
          Premises to  Building standard condition within one hundred eighty
          (180) days of the date of the damage, subject to extensions for Tenant
          delays, shortages of labor or materials, force majeure or other
          conditions beyond Landlord's reasonable control, Tenant shall have the
          right to terminate the Lease effective immediately upon such written
          notice to Landlord.  If Tenant fails to give such notice within thirty
          (30) days after the expiration of the above-referenced one hundred
          eighty (180) day period (as it may be extended), Tenant shall be
          deemed to have elected not to terminate the Lease.

8.   COMPLIANCE WITH LAWS AND USAGE

     Tenant, at its own expense, will comply with all federal, state, municipal
and other laws, ordinances, rules and regulations applicable to the Leased
Premises (except with respect to pre-existing conditions caused by Landlord) and
the business conducted therein by Tenant (including, without limitation, any
temperature control restrictions); will comply with the Building rules and
regulations attached as Exhibit "C," as such rules and regulations may, from
time to time, be amended by Landlord; and will not commit or permit waste in the
Leased Premises or Building.  Landlord agrees to use diligent good faith efforts
to ensure that the Leased Premises are delivered to Tenant free of any
violations, orders or notices of violations of all public or quasi-public
authorities.  Tenant will not commit any act which is a nuisance or annoyance to
Landlord or to other tenants, or which might, in the exclusive judgment of
Landlord, appreciably damage Landlord's goodwill or reputation, or tend to
injure or depreciate the Project; will not engage in any activity which would
cause Landlord's fire and extended coverage insurance to be canceled or the rate
therefor to be increased (or, at Landlord's option, will pay any such increase);
and will not paint, erect or display any sign, advertisement, placard or
lettering which is visible in the corridors or lobby of the Building or from the
exterior of the Building without Landlord's prior written approval.

9.   LIABILITY AND INDEMNITY

     A.   Tenant shall defend, indemnify and hold Landlord and Landlord's
          designated property management firm and their respective agents,
          employees and affiliated entities (collectively, the "Indemnified
          Party" [or "Indemnified Parties"]) from all losses, claims, suits,
          actions, damages and liability, including costs and expenses of
          defending against the foregoing (collectively, the "Claims"), arising
          or allegedly arising from:  (i) any act or omission of Tenant or
          Tenant's agents, employees, assignees, sublessees, licensees,
          contractors, subcontractors, customers, invitees or other persons from
          time to time in the Leased Premises; (ii)

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          Tenant's failure (or the failure of Tenant's agents, employees,
          contractors, subtenants, assignees, invitees or other occupants of the
          Leased Premises) to comply fully with all laws and regulations that
          apply to the Leased Premises) to comply fully with al laws and
          regulations that apply to the Leased Premises or the use or occupancy
          of the Leased Premises; (iii) Tenant's breach, violation or
          nonperformance of any covenant of Tenant under this Lease; and (iv)
          any injury to or death of any person or damage to or destruction of
          the property of any person occurring in the Leased Premises. Tenant's
          obligation stated in this subparagraph shall include, without
          limitation, the obligation to defend the Indemnified Parties against
          all Claims where it is asserted, alleged or determined that the acts
          or omissions of an Indemnified Party; but Tenant shall pay all other
          damages.

     B.   Landlord shall defend, indemnify and hold Tenant and Tenant's agents,
          employees and affiliated entities (collectively, the "Indemnified
          Party" [or "Indemnified Parties"]) from all losses, claims, suits,
          actions, damages and liability, including costs and expenses of
          defending against the foregoing (collectively, the "Claims"), arising
          or allegedly arising from any injury to or death of any person or
          damage to or destruction of the property of any person occurring in
          the Building (except for the Leased Premises).  Landlord's obligation
          stated in this subparagraph shall include, without limitation, the
          obligation to defend the Indemnified Parties against all Claims where
          it is asserted, alleged or determined that the acts or omissions of an
          Indemnified Party, whether or not negligent, may have been a cause
          (whether sole, joint or concurrent) of any of such Claims and to pay
          the full cost of any settlement reached by Landlord with respect to
          any such Claims.  Landlord's obligations under this subparagraph will
          not include, however, an obligation to pay that portion of any damages
          the responsibility for which is attributed by a court of competent
          jurisdiction, in a final, nonappealable judgment, to the negligent
          acts or omissions of an Indemnified Party; but Landlord shall pay all
          other damages.

     C.   Landlord and Tenant each hereby release and waive all claims, rights
          of recovery and causes of action that either party (or any party
          claiming by, through or under such party, directly or by subrogation,
          or otherwise) may now or hereafter have against the other party (or
          any of the other party's directors, officers, employees or agents or,
          with respect to Landlord, Landlord's designated property management
          firm) for any loss or damage that may occur to the Project, the Land,
          the Building, the Parking Garage, the Leased Premises, the leasehold
          improvements or any of the contents of any of the foregoing occurring
          by reason of fire or other casualty or resulting from the acts or
          omissions of any other tenant or occupant of the Project (or such
          party's agents, employees, contractors, customers or invitees) or
          resulting from any other cause (including, without limitation, the
          negligence of the waiving party or the negligence of the other party
          or the negligence of either party's directors, officers, employees or
          agents or, with respect to Landlord, Landlord's

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<PAGE>

          designated property management firm) that could have been insured
          against under the terms of (1) a standard fire and extended coverage
          insurance policy, with vandalism and malicious mischief endorsement
          and sprinkler leakage endorsement (where applicable) or all-risk
          insurance policy, or (2) any other loss that is covered by insurance
          of the party suffering the loss. The waiver and release of Landlord
          made by Tenant in this subparagraph will include Landlord's designated
          property management firm. The waiver set forth in this subparagraph
          shall preclude all rights of recovery of third parties by way of
          subrogation, and assignment or otherwise, but shall not apply to any
          deductibles on insurance policies carried by Landlord nor to any co-
          insurance penalty which Landlord might sustain.

     D.   Landlord will maintain in force and effect at all times while this
          Lease is in force and effect such insurance as is required to be
          maintained pursuant to the underlying deeds.

     E.   Tenant will maintain in force and effect at all times during the term
          of this Lease, all risk insurance covering its leasehold improvements
          in excess of Fifteen and 00/100 Dollars ($15.00) per square foot
          Rentable Area contained within the Leased Premises, furniture,
          furnishings and equipment located in the Leased Premises in amounts
          equal to at least eighty percent (80%) of insurable value and public
          liability and property damage insurance with limits of not less than
          One Million Dollars ($1,000,000) for personal injury (including death)
          to any number of persons in any one occurrence and Five Hundred
          Thousand and 00/100 Dollars ($500,000.00) for damage to or destruction
          or property for any one occurrence.  Tenant shall furnish reasonably
          satisfactory evidence to Landlord of maintenance of such insurance
          coverage at any time and from time to time upon request.

10.  ADDITIONS AND FIXTURES

     A.   Tenant shall make no alteration, improvement, repair or replacement to
          the Leased Premises (including, without limitation, any mechanical,
          electrical or plumbing systems located within or serving the Leased
          Premises) without the prior written consent of Landlord.  If
          Landlord's prior written consent is granted, the work shall be
          performed in a good and workmanlike manner at Tenant's expense but by
          workmen of Landlord or by workmen approved in advance in writing by
          Landlord, in accordance with plans and specifications which have been
          previously submitted to, and approved in advance in writing by
          Landlord and subject to the Building rules and regulations.  Landlord
          shall have the right to require certificates of insurance, copies of
          building permits, copies of the final certificate of occupancy,
          executed lien releases and reimbursement of the expenses incurred by
          Landlord in reviewing Tenant's proposed plans and specifications as
          conditions to granting its consent to the performance of such work.
          Landlord's

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<PAGE>

          consent shall also be conditioned upon those furnishing labor or
          materials for Tenant's job working in harmony and not interfering with
          any labor utilized by Landlord or its contractors or by any other
          tenant or other tenant's contractors. If those furnishing labor or
          materials for Tenant's work cause disharmony or interference,
          Landlord's consent may be withdrawn immediately upon notice to Tenant.
          Tenant will not permit any mechanic's or materialmen's lien to be
          placed on the Leased Premises, improvements or Building during the
          Lease term caused by or resulting from any work performed, materials
          furnished or obligation incurred by or at the request of Tenant. In
          the case of the filing of any lien, Tenant shall cause the same to be
          discharged (by bond or otherwise) within twenty (20) days of such
          filing. Any failure to do so within this period will give Landlord the
          right, but not the obligation (among other rights or remedies of
          Landlord), to discharge the same by paying the amount claimed due or
          obtaining the discharge of such lien by deposit in court or bonding.
          Any amounts paid by Landlord, and all reasonable legal fees and
          expenses in defending any such action or the discharge of such lien,
          plus interest thereon from the date of Landlord's written notice to
          Tenant of such payment until Tenant's reimbursement, at the lesser of
          15% per annum or the maximum legally permitted interest rate, shall be
          paid by Tenant to Landlord on demand.

     B.   Tenant may remove its trade fixtures, supplies, movable office
          furniture and equipment not attached to the Building provided: (1)
          removal is made prior to the expiration or termination of this Lease;
          (2) Tenant is not in default of any obligation or covenant under this
          Lease at the time of removal; and (3) Tenant promptly repairs all
          damage caused by removal.  All other property at the Leased Premises
          and any alteration or addition to the Leased Premises (including wall-
          to-wall carpeting, paneling or other wall covering) and any other
          article attached or affixed to the floor, wall or ceiling of the
          Leased Premises shall remain upon and be surrendered with the Leased
          Premises at the expiration or termination of this Lease, Tenant hereby
          waiving all rights to any payment or compensation therefor.  If
          however, Landlord so requests in writing, Tenant will, prior to
          expiration or termination of this Lease, remove any and all
          alterations, additions, fixtures, equipment and property placed or
          installed by it in the Leased Premises (other than the leasehold
          improvements installed prior to the Commencement Date and except to
          the extent Landlord requires such removal in connection with its
          approval of any subsequent alterations, additions or fixtures) and
          will repair any damage caused by such removal.

     C.   If any property not belonging to Landlord remains t the Leased
          Premises after the expiration or termination of the term of this
          Lease, Tenant hereby authorizes Landlord to dispose of the property as
          Landlord may desire without liability to Tenant if the property
          belongs to Tenant.  If the property does not belong to Tenant, Tenant
          agrees to indemnify and hold harmless from all suits, actions,

                                      -10-
<PAGE>

          liability, loss, damages and expenses in connection with any removal,
          exercise of dominion over and/or disposition of such property by
          Landlord.

     D.   Tenant may, at its expense, install additional locks or security
          systems in the Leased Premises provided that (1) such installation
          shall comply with applicable provisions of the Building Rules and
          Regulations attached hereto as Exhibit "C"; (2) Landlord shall be
          furnished with duplicate keys and entry codes to gain entrance where
          permitted under this Lease; and (3) Tenant removes such locks and
          security systems upon the expiration or earlier termination of the
          lease, and repairs all damages and otherwise restores the Leased
          Premises to their condition prior to such installation.

11.  ASSIGNMENT AND SUBLETTING

     A.   Neither Tenant nor Tenant's legal representatives or successors in
          interest by operation of law or otherwise shall assign this Lease or
          sublease the Leased Premises or any part thereof or mortgage, pledge
          or hypothecate its leasehold interest or grant any concession or
          license within the Leased Premises without the prior written
          permission of Landlord.  Provided that there is no Event of Default
          hereunder (or circumstances which, with the passage of time or giving
          of notice, or both, would constitute an Event of Default), Landlord's
          permission shall not be unreasonably withheld or delayed to an
          assignment of this Lease or to a sublease proposed by Tenant.
          However, it is agreed that a withholding or such permission by
          Landlord to a proposed assignment or sublease on the grounds that in
          Landlord's good faith judgment the usage permitted thereunder would
          constitute an "objectionable use" (as defined below), or on the
          grounds that the proposed assignee or sublessee does not have the
          financial net worth reasonably acceptable to Landlord, shall be deemed
          reasonable and shall not be deemed unreasonable.  For purposes hereof,
          the term "objectionable use" shall refer to any use which would (i)
          conflict with the exclusive usage rights granted to any other tenant
          in the Building; (ii) diminish the value or reputation or alter the
          first class character of the Building; (iii) be inconsistent with the
          general use of the Building by other tenants; (iv) be for any other
          use not customarily found in comparable Class A office buildings owned
          by Landlord in the Greenway Plaza area of Houston, Texas, including
          without limitation eleemosynary or governmental or quasi-government
          purposes, a medical or dental practice, an employment office, a school
          or training facility or a religious institution; or (v) materially
          increase the use of the elevators or common areas of the Project or
          the traffic flow of vehicles and/or people in and out of the Building
          or parking garages.  Any attempt to do any of the foregoing without
          the prior written permission of Landlord shall be void.  In the event
          Landlord's permission is requested for an assignment, sublease or
          other transaction, signed copies of all instruments relative thereto
          (executed by all parties except Landlord) shall be submitted to
          Landlord prior to or

                                      -11-
<PAGE>

          contemporaneously with the request for Landlord's written permission
          (it being understood that no such instrument shall be effective
          without the written permission of Landlord). Landlord shall then have
          the right (but no obligation), as of the effective date of the
          requested transaction, to terminate this Lease for the portion of the
          Leased Premises and for that portion of the term of this Lease as to
          which Landlord has been requested to permit such transaction. If
          Landlord elects to terminate this Lease for that portion of the Leased
          Premises and for the portion of the term of this Lease, then the rent
          and other charges payable shall be proportionately reduced. If Tenant
          attempts to permit anyone to occupy any portion of the Leased Premises
          without the prior written permission of Landlord, Landlord shall have
          the right to terminate this Lease effective upon fifteen (15) days
          notice to Tenant at any time thereafter for either the entire Leased
          Premises or only the portion which Tenant has attempted to permit some
          other party to occupy. Should Landlord elect to exercise its
          termination rights, then the rent shall be proportionately reduced. If
          Landlord's permission is granted and the rent payable by the other
          party (or a combination of the rent payable plus any bonus or other
          consideration) exceeds the rent payable under this Lease, then Tenant
          shall pay Landlord fifty percent (50%) of all excess within ten (10)
          days following receipt by Tenant (after deducting all reasonable costs
          directly incurred by Tenant in connection with such assignment or
          sublease, such as tenant improvement costs, moving allowance(s),
          architectural fees, and brokerage commissions, but excluding cash
          inducements or other consideration paid).

     B.   If Tenant is a corporation whose stock is not publicly traded, any
          change in ownership or power to vote a majority of the voting stock in
          Tenant shall constitute an assignment for the purposes of this Lease.
          If Tenant is a partnership having one or more corporations as partner,
          the provisions of the preceding sentence shall apply to each
          corporation as if it alone had been the Tenant.  If Tenant is a
          partnership (whether or not having any corporation as general
          partner), the transfer of a partnership interest constituting a
          majority shall constitute an assignment for the purposes of this
          Lease.

          Notwithstanding any other provision of this Lease to the contrary, the
          prohibition on assignments shall not be applicable (and no prior
          consent of or notice to Landlord shall be required) with respect to
          (i) a merger between Tenant and another entity or (ii a transfer of a
          controlling interest of stock in Tenant, provided the surviving entity
          (in the case of a merger) or Tenant (in the case of a transfer in
          control) has a net worth greater than or equal to the net worth of
          Tenant immediately prior to such merger or transfer of control  Upon
          written request from Landlord, Tenant shall furnish evidence that a
          particular assignment complies with the provisions of the preceding
          sentence.

                                      -12-
<PAGE>

     C.   If Landlord gives written permission to a particular assignment,
          sublease or other transaction, it shall not be deemed as permission to
          any other or subsequent transaction or a release of Tenant from its
          covenants, duties and obligations under this Lease.  If this Lease is
          assigned or if the Leased Premises are subleased (whether in whole or
          in part) or in the event of the mortgage, pledge or hypothecation of
          the leasehold interest or grant of any concession or license within
          the Leased Premises without the prior written permission of Landlord,
          or if the Leased Premises are occupied in whole or in part by anyone
          other than Tenant without the prior written permission of Landlord,
          Landlord may nevertheless collect rent from the occupant and apply the
          net amount collected to the rent payable hereunder, but no collection
          of rent by Landlord shall be deemed a waiver of these provisions or a
          release of Tenant from the further performance of its covenants,
          duties and obligations hereunder.

     D.   Notwithstanding the foregoing provisions of this Paragraph 11, Tenant
          shall have the right at any time and from time to time, as many times
          as may be convenient, to sublet or assign all or part of the Leased
          Premises to an "Affiliate" of Tenant (as defined below); provided,
          however, that (i) Tenant shall nonetheless give Landlord written
          notice of such transfer together with a fully-executed copy of the
          transfer instrument and such other supporting documentation as
          Landlord may reasonably request, (ii) the undersigned Tenant will
          nevertheless remain directly and primarily liable for the performance
          of all of the covenants, duties and obligations of Tenant hereunder
          (including, without limitation, the obligation to pay all rent and
          other sums herein provided to be paid); and (iii) Landlord shall be
          permitted to enforce the provision of this instrument against the
          undersigned Tenant and/or any assignee without demand upon or
          proceeding in any way against any other person.  As used herein, the
          term "Affiliate" shall mean any person or entity controlling,
          controlled by, or under common control with another such person or
          entity.  "Control" as used herein shall mean the possession, direct or
          indirect, of the power to direct or cause the direction of the
          management and policies of such controlled person or entity;
          ownership, directly or indirectly, of more than fifty percent (50%) of
          the voting securities of, or possession of the right to vote, in the
          ordinary direction of its affairs, more than fifty percent (50%) of
          the voting interest in any person or entity shall be presumed to
          constitute such control.

12.  SUBORDINATION

     Tenant accepts this Lease subject to all matters of record which affect the
Building and subject and subordinate to any mortgage or deed of trust, presently
existing or hereafter placed upon the Project, and to any renewals,
modifications and extensions thereof.  Tenant agrees that any such mortgagee
and/or beneficiary of any deed of trust ("Landlord's Mortgagee") shall have the
right at any time to subordinate such mortgage or deed of trust to this Lease,
on terms and conditions Landlord's Mortgagee may deem appropriate in its sole
discretion.  Tenant agrees to

                                      -13-
<PAGE>

execute such instruments subordinating this Lease as Landlord or Landlord's
Mortgagee may request, upon demand, provided such instruments are in form and
substance customary in the industry for comparable transactions.

13.  OPERATING COST

     A.   If, after the calendar year 1996 ("Base Year"), the Project Operating
          Cost (as defined below) increases, then Tenant agrees to pay to
          Landlord, as additional rent, its pro rata share of increases in the
          Project Operating Cost over and above the amount of the Project
          Operating Cost attributable to the Base Year.  Tenant's pro rata share
          of such increases shall be a fraction of the total increases, the
          numerator of which shall be the Rentable Area of the Leased Premises,
          and the denominator of which shall be the total Rentable Area of the
          Building.

     B.   "Project Operating Cost" shall consist of the operating expenses of
          the Project, reasonably allocable to the Building and Parking Garage,
          computed on the accrual basis and determined in accordance with
          generally accepted accounting principles which shall be consistently
          applied.  The term "operating expenses" shall mean all expenses, costs
          and disbursements (but not costs of replacement of capital investment
          items, nor specific costs especially billed to and paid by specific
          tenants, nor rental [line missing] to pay because of, or in connection
          with, the ownership, management, maintenance, repair and operation of
          the Project, including, but not limited to, the following:

          (1)  Wages and salaries of all workers and employees engaged in the
               direct operation and maintenance of the Project, including taxes,
               insurance and benefits relating thereto;

          (2)  Management fees relating to the direct operation and management
               of the Project;

          (3)  Costs of all supplies and materials used in direct operation,
               maintenance and repair of the Project;

          (4)  Cost of water and power, heating, lighting, air conditioning and
               ventilating for the Project;

          (5)  Cost of all maintenance and service agreements relating to the
               Project and all equipment therefor (including, without
               limitation, janitorial service, window cleaning and elevator
               maintenance);

          (6)  Cost of casualty and liability insurance applicable to the
               Project and Landlord's personal property used in connection
               therewith;

                                      -14-
<PAGE>

          (7)  All federal, state, county or municipal taxes, assessments and
               other governmental charges, whether by existing taxing
               authorities or by others subsequently created, and any other
               taxes and improvement assessments attributable to that portion of
               the Land allocated to the Building, the Building and the Parking
               Garage or their operation (excluding federal and state income
               taxes).  Tenant will be responsible for ad valorem taxes on its
               personal property and on the value of leasehold improvements to
               the extent they are separately assessed by any taxing authority;

          (8)  Cost of repairs and general maintenance (excluding costs of
               repairs paid by proceeds of insurance or by Tenant or other third
               parties, and alterations attributable solely to tenants of the
               Project other than Tenant), including the cost of inspections and
               renovations required by governmental authority;

          (9)  Amortization of the cost of capital investment items and their
               installation which are primarily for the purposes of safety,
               saving energy or reducing operating costs or which may be
               required by governmental authority.  All such costs shall be
               amortized over the reasonable life of the capital investment
               items, with the reasonable life and amortization schedule being
               determined in accordance with generally accepted accounting
               principles.

     C.   Tenant shall be obligated to discharge its payment obligation with
          respect to increases in the Project Operating Cost in accordance with
          the billing procedures used by Landlord.  Landlord shall have the
          right to invoice Tenant for such increases periodically, as Landlord
          may desire, but not less frequently than annually; and Landlord may
          alter its billing procedures at any time during the Lease term.
          Landlord may (but shall have no obligation to) submit a statement or
          invoice to Tenant for each month of the Lease term for one-twelfth
          (1/12th) of Tenant's pro rata share of Project Operating Cost
          increases, and Tenant shall pay the indicated amount contemporaneously
          with Base Rental.  The monthly one-twelfth (1/12th) amount stated in
          Landlord's monthly statement or invoice shall be Landlord's estimate
          of Tenant's monthly pro rata share of Project Operating Cost
          increases, and shall be based on the actual Project Operating Cost
          incurred during the prior calendar year and Landlord's good faith
          business judgment of the estimated Project Operating Cost for the then
          current year.  Landlord reserves the right to adjust the estimate of
          the Project Operating Cost at any time during the then current year if
          the actual Project Operating Cost then being incurred varies from
          Landlord's prior estimate.

          Each calendar year Landlord shall perform computations necessary to
          determine the amount of increases in the Project Operating Cost
          properly payable by Tenant.   If Tenant has overpaid pursuant to
          Landlord's periodic billing of such increases,

                                      -15-
<PAGE>

          then Landlord shall credit Tenant's account for the amount of the
          excess; but, if Tenant shall have underpaid pursuant to Landlord's
          periodic billing of such increases, then Landlord shall ill Tenant for
          the amount of the underpayment (which underpayment shall be due within
          thirty (30) days following such billing). Tenant's pro rata share of
          such increases in the Project Operating Cost for partial calendar
          years and for partial months of the Lease term occurring at the
          beginning or end of the Lease term shall be [line missing] as to
          reduce the monthly installments of Base Rental payable by Tenant
          hereunder below the amount set forth in Paragraph 3 of this Lease.

     D.   Notwithstanding the foregoing provisions of this Paragraph 13, the
          Project Operating Cost for the Base Year shall be equal to actual
          operating costs for that calendar year, with those Project Operating
          Costs that vary with occupancy being adjusted upward to reflect the
          costs of operating the Project at a Building occupancy level of 95%;
          however, if the occupancy level of the Building for the Base Year
          equals or exceeds 95%, there shall be no upward adjustment.  Likewise,
          the Project Operating Cost for subsequent calendar years shall be
          adjusted upward to reflect a 95% Building occupancy level; however, if
          the occupancy level of the Building for any calendar year after the
          Base Year equals or exceeds 95%, there shall be no such upward
          adjustment and actual costs shall be used to determine the Project
          Operating Cost for such year.

     E.   Within sixty (60) days from the rendition of any such statement,
          Tenant may question the amount and propriety of any item appearing or
          excluded therefrom.  Landlord agrees that, for a period of two (2)
          years following expiration of the applicable calendar year, it will
          maintain complete and accurate records of all costs and expenses which
          shall be paid or incurred by it in connection with the operation of
          the Project.  Tenant, at its expense, shall have the right at all
          reasonable times to audit Landlord's books and records relating to
          this Lease for any year for which additional rental payments become
          due, insofar as such books and records pertain to costs involved in
          rent escalation.  Any overpayment by Tenant shall be credited to its
          account.

14.  EMINENT DOMAIN

     A.   If any material part of the Project is taken by eminent domain or
          voluntarily conveyed to the condemning authorities in settlement of an
          eminent domain action, Landlord shall have the option to terminate
          this Lease by giving a notice of Lease termination to Tenant within
          sixty (60) days from the date of the taking.  It is further agreed
          that Tenant shall have the right to terminate this Lease if all or a
          portion of the Leased Premises is so taken and the remainder of the
          Leased Premises is insufficient for the conduct of Tenant's business.
          If Tenant so elects to terminate this Lease, it shall notify Landlord
          within thirty (30) days after the

                                      -16-
<PAGE>

          date of taking; otherwise, Tenant shall be deemed to have elected not
          to terminate this Lease. If this Lease should be terminated under this
          Paragraph 14, rental shall be payable up to the date that possession
          is taken by the condemning authority; and Landlord will refund to
          Tenant any prepaid unaccrued rent, less any sum then owing by Tenant
          to Landlord.

     B.   If the Lease is not terminated, and the taking involved a portion of
          the Leased Premises, rental shall be reduced in proportion to the area
          of the Leased Premises taken and Landlord shall repair any damage to
          the remainder of the Leased Premises resulting from such taking or any
          taking which impacts Tenant's use of the Parking Garage or the common
          areas of the Building.  Landlord's repair obligation in such
          circumstance swill be limited to the performance of construction work
          necessary to return the damaged portion of the remaining Leased
          Premises to the condition in which such portion was placed by
          Landlord, at Landlord's expense, on or before the Commencement Date.

     C.   All sums awarded or agreed upon between Landlord and the condemning
          authority for the taking of the interest of Landlord or Tenant,
          whether as damages or as compensation, will be the property of
          Landlord without prejudice, however, to claims of Tenant against the
          condemning authority for the unamortized cost of leasehold
          improvements which were paid for by Tenant and taken by the condemning
          authority.

15.  ACCESS BY LANDLORD

     Landlord, Landlord's Mortgagee, their agents and employees shall have
access to and the right to enter upon the Leased Premises at any reasonable time
after prior notice (except in an emergency) to examine its condition, to make
any repairs or alterations required to be made by Landlord, to show the Leased
Premises to prospective purchasers or tenants and for any other purpose deemed
reasonable by Landlord.

16.  LANDLORD'S LIEN

     Tenant, as debtor, hereby grants to Landlord, as secured party, a contract
lien and security interest on all fixtures, furniture, equipment, merchandise,
inventory and other property of Tenant (including Tenant's ownership interests,
interests as lessee and options to purchase any of such property) presently
situated at or hereafter placed in the Leased Premises, and upon all proceeds of
any insurance which may accrue to Tenant by reason of destruction or damage to
any such property, as [line missing] and the performance of all other
obligations of Tenant under this Lease. All exemption laws are hereby waived in
favor of such lien and security interest and in favor of Landlord's statutory
lien.  This contract lien and security interest may be foreclosed with or
without court proceedings by public or private sale or any other lawful method,
provided that Landlord gives Tenant at least ten (10) days notice of the time
and place of said sale; and

                                      -17-
<PAGE>

Landlord shall have the right to become the purchaser, upon being the highest
bidder at such sale. A carbon copy, photographic or other reproduction of this
Lease is sufficient as a financing statement. If any of the obligations of
Tenant under this Lease are guaranteed pursuant to a guaranty instrument, Tenant
hereby consents and agrees to al of the terms and provisions of such guaranty.
Landlord agrees to subordinate its lien rights to a third party providing
furniture, fixtures and/or equipment to Tenant or providing funds for the
acquisition of same, which subordination shall be in writing, signed by all
parties, and in a form reasonably acceptable to landlord.

17.  EVENTS OF DEFAULT

     A.   Each of the following acts or omissions of Tenant or occurrence shall
          constitute an "Event of Default":

          (1)  Failure or refusal by Tenant to timely pay rent within five (5)
               days of the due date;

          (2)  Failure to perform or observe any other covenant or condition of
               this Lease within thirty (30) days following written notice from
               Landlord of such failure or such longer period as is reasonably
               necessary to cure such failure, provided that Tenant shall
               commence the cure of said failure within such thirty (30) day
               period and shall continuously and diligently pursue the remedy of
               such failure; or

          (3)  Abandonment or vacating of the Leased Premises or any significant
               portion thereof while failing to pay Base Rental and other
               payments due hereunder when due.  Although Tenant continues to
               pay rent, if Tenant abandons or vacates fifty percent (50%) or
               more of the Leased Premises, Landlord shall have the right to
               recapture the Leased Premises, in which event, Tenant shall
               thereafter be relieved of its covenants, duties and obligations
               under this Lease.

     B.   Upon any Event of Default, Landlord may, at its option, in addition to
          all other rights and remedies given hereunder or by law or equity, do
          any one or more of the following:

          (1)  Terminate this Lease, in which event Tenant shall immediately
               surrender possession of the Leased Premises to Landlord;

          (2)  Enter upon and take possession of the Leased Premises,
               terminating Tenant's right to possession of the Leased Premises,
               and expel or remove Tenant and any other occupant therefrom, with
               or without having terminated the Lease;

                                      -18-
<PAGE>

          (3)  Alter locks and other security devices at the Leased Premises,
               remove Tenant's property and the property of other located within
               the Leased Premises, and cease providing services.  The
               provisions of this Paragraph 17 will override and control any
               conflicting provisions of Section 93.002 of the Texas Property
               Code, as well as any successor statute governing the right of a
               landlord to change the door locks of a tenant under a commercial
               lease.

     C.   Exercise by Landlord of any one or more remedies granted under this
          Lease or otherwise available shall not be deemed to constitute
          Landlord's acceptance of surrender of the Leased Premises by Tenant,
          whether by agreement or by operation of law.  Such surrender can be
          effected only by the written agreement of Landlord and Tenant
          hereafter entered into.  Tenant acknowledges that if Landlord has
          altered locks and other security devices at the Leased Premises after
          an Event of Default, Landlord may require full payment of all sums
          then due to Landlord under this Lease as a condition to Tenant's
          entitlement to a key to new or altered locks that Landlord may have
          placed on the Leased Premises after an Event of Default.  After any
          Event of Default, Landlord's alteration of locks and security devices
          and exercise of control over the property of Tenant or others at the
          Leased Premises shall not be deemed unauthorized or constitute a
          conversion.  All claims for damages by reason of reentry, repossession
          and/or alteration of locks or other security devices are hereby
          waived, as are all claims for damages by reason of any distress
          warrant, forcible detainer proceedings, sequestration proceedings or
          other legal process.  Tenant agrees that any reenty by Landlord may be
          pursuant to judgment obtained in forcible detainer proceedings or
          other legal proceedings or without the necessity for legal
          proceedings, as Landlord may elect, and Landlord shall not be liable
          in trespass or otherwise.

     D.   If Landlord elects to terminate the Lease for an Event of Default,
          then, despite such termination, Tenant shall be liable for and shall
          pay to Landlord the sum of (x) all rent and other indebtedness accrued
          to the date of termination, plus (y) as damages, an amount equal to
          the present value (computed as of the date of any such termination
          using a discount factor equal to 9% per annum) of the difference
          between the amount stated in clause (i), below, and the amount stated
          in clause (ii) below, as follows:

          (i)  the total Base Rental, plus Tenant's share of Project Operating
               Cost increases (using such sum for the year of such termination
               as the basis for determining the amount thereof which would have
               been due each year thereafter for the remainder of the Lease term
               had it not been terminated), for the remaining portion of the
               Lease term if such term had not been terminated by Landlord prior
               to the Expiration Date stated in Paragraph 2; and

                                      -19-
<PAGE>

          (ii) the fair market rental value of the Leased Premises, computed as
               of the date of such termination, for the remaining portion of the
               Lease term if such term had not been terminated by Landlord prior
               to the Expiration Date stated in Paragraph 2.

          If Landlord elects to terminate the Lease for an Event of Default, in
          lieu of exercising the rights of Landlord under the preceding portion
          of this subparagraph D, or if Landlord elects to terminate Tenant's
          right to possession of the Leased Premises without terminating the
          Lease, then Landlord may instead hold Tenant liable for (x) all rent
          and other indebtedness accrued to the date of Lease termination or the
          date on which Tenant's possession is terminated, as the case may be,
          plus (y) such Base Rental and Tenant's share of Project Operating Cost
          increases (using such sum for the year of such termination as the
          basis for determining the amount thereof which would have been due
          each year thereafter for the remainder of the Lease term) as would
          otherwise have been required to be paid by Tenant to Landlord during
          the period following the termination of the Lease or Tenant's right to
          possession of the Leased Premises to the date of expiration of the
          Lease term stated in Paragraph 2, diminished by any net sums
          thereafter received by Landlord through reletting the Leased Premises
          during said period (after deducting expenses incurred by Landlord as
          provided in subparagraph E).  Reentry by Landlord will not affect the
          obligations of Tenant for the unexpired Lease term.  Actions to
          collect amounts due by Tenant may be brought from time to time by
          Landlord during the aforesaid period, on one or more occasions,
          without the necessity of Landlord waiting until expiration of such
          period.  Tenant shall not be entitled to any sums obtained by
          reletting in excess of the Base Rental provided for in this Lease.

     E.   In case of an Event of Default, Tenant shall also be liable for and
          shall pay to Landlord: broker's fees incurred by Landlord in
          connection with reletting the whole or any part of the Leased
          Premises; the cost of removing and storing Tenant's or other
          occupant's property; the cost of repairing, altering, remodeling or
          otherwise putting the Leased Premises into condition acceptable to a
          new tenant or tenants; and all other reasonable expenses (including
          attorney's fees and court costs) incurred by Landlord in enforcing
          Landlord's remedies.  Actions to collect amounts due by Tenant may be
          brought from time to time by Landlord without the necessity of
          Landlord waiting until expiration of the Lease term.

     F.   Past-due rent and other past-due sums payable by Tenant under this
          Lease shall bear interest form the date due until paid at the lesser
          of fifteen percent (15%) per annum or the maximum nonusurious interest
          rate permitted by law.

     G.   In the event of termination of the Lease or termination of Tenant's
          right to possession of the Leased Premises or repossession of the
          Leased Premises for an

                                      -20-
<PAGE>

          Event of Default, Landlord shall make reasonable efforts to relet the
          Leased Premises, or portions thereof, and to collect rental after
          reletting; and in the event of reletting, Landlord may relet the whole
          or any portion of the Leased Premises for any period, to any tenant,
          and for any use and purpose; provided, however, that Landlord shall
          have no obligation to relet Tenant's space in preference to other
          space which Landlord has available for lease in the building. Tenant
          hereby waives and released Landlord from any obligation that may be
          otherwise imposed by law which would obligate Landlord to relet the
          Leased Premises or attempt to relet the Leased Premises after an Event
          of Default. If Landlord, in its sole discretion, elects to relet it,
          it can relet the whole or any portion of the Leased Premises for any
          period, to any tenant, and for any use.

     H.   If Tenant fails to make any payment, perform any obligation or cure
          any default hereunder within the time permitted, Landlord, without
          being under any obligation to do so and without thereby waiving such
          failure or default, may make the payment, [line missing] enter the
          Leased Premises for such purpose).  Tenant agrees to pay Landlord,
          upon demand, all costs, expenses and disbursements (including
          reasonable attorney's fees) incurred by Landlord in taking such
          remedial action.

     I.   In the event of any default by Landlord, Tenant's exclusive remedy
          shall be an action for damages (Tenant hereby waiving the benefit of
          any laws granting it a pre-judgment lien upon the property of Landlord
          and/or upon rent due Landlord)' but, prior to any such action, Tenant
          will give Landlord and Landlord's Mortgagee, as provided in Paragraph
          21 below, written notice specifying such default with particularity;
          and Landlord shall have a reasonable period (but not less than thirty
          (30) days, plus such additional period, as may be required in the
          exercise of reasonable diligence) in which to commence to cure any
          such default.  Unless and until Landlord fails to commence to cure any
          default after notice (or, having so commenced, thereafter fails to
          exercise reasonable diligence), Tenant shall not have any remedy or
          cause of action by reason thereof.  All obligations of Landlord
          hereunder will be construed as covenants, not conditions; and all
          obligations will be binding upon Landlord only during the period of
          its ownership of the Building and not thereafter.

     J.   In connection with either party instituting action seeking judicial
          relief at law or in equity in connection with this Lease, the
          prevailing party shall be entitled to reasonable attorney's fees and
          court costs.

18.  NONWAIVER

     Neither acceptance of rent by Landlord nor failure by Landlord to complain
of any default of Tenant shall constitute a waiver of any of Landlord's rights
hereunder.  Waiver by Landlord of

                                      -21-
<PAGE>

any right for any default of Tenant shall not constitute a waiver of any right
for either a subsequent default of the same obligation or any other default.

19.  HOLDING OVER

     If Tenant remains in possession of the Leased Premises after the expiration
of the term of this Lease without Landlord and Tenant executing a new lease,
then Tenant shall be deemed to be occupying the Leased Premises as a tenant-at-
sufferance, subject to all the covenants and obligations of this Lease
(including, without limitation, the provisions of Paragraph 13 relating to the
Project Operating Cost), but at a daily base rental rate equal to the greater of
(x) the prevailing Building base rental rate, as reflected in Landlord's
published rent schedule then in effect, or (y) 150% of the per diem Base Rental
provided hereunder, computed on the basis of a thirty (30)-day month.
Notwithstanding provisions to the contrary applicable during the original term
or any extension term of this Lease, Landlord shall have the right to terminate
the tenancy-at-sufferance immediately upon deliver of notice to Tenant.  The
provisions of this paragraph will not preclude Landlord from recovering from
Tenant all damages suffered by Landlord as a consequence of Tenant's holdover in
the Leased Premises.

20.  NOTICE

     Any notice which may or shall be given under the terms of this Lease shall
be in writing and shall be either delivered by hand or sent by United States
Certified Mail, Return Receipt Requested, postage prepaid, or by Federal Express
or other expedited courier service where proof of delivery can be obtained, as
follows:  if for Landlord, to the Building office; and if for Tenant, to the
Leased Premises.  Such addresses may be changed from time to time by either
party by giving notice as provided above.  Notice shall be deemed given when
delivered (if delivered by hand) or when postmarked (if sent by mail).  Despite
the foregoing, notice given to Tenant by hand will be effectively given wherever
the intended recipient is found and will be deemed received upon the date of
actual receipt.

21.  LANDLORD'S MORTGAGEE

     At any time the Building is subject to a mortgage and/or deed of trust, and
Tenant gives notice to Landlord alleging default by Landlord, Tenant will also
simultaneously give a coy of such notice to each Landlord's Mortgagee (provided
Landlord or Landlord's Mortgagee shall have advised Tenant in writing of the
name and address of Landlord's Mortgagee) and each Landlord's Mortgagee shall
have the right (but no obligation) to cure such default during the period that
is permitted to Landlord, plus an additional period of thirty (30) days.  Tenant
will accept curative action (if any) taken by Landlord's Mortgagee with the same
effect as if such action had been taken by Landlord.  Tenant will, at such time
or times as Landlord, may request, sign a certificate stating whether this Lease
is in full force and effect; whether any amendments or modifications exist;
whether, to Tenant'' knowledge, there are any defaults hereunder; and such other
information and agreements as may be reasonably requested.

                                      -22-
<PAGE>

22.  CONDITION OF PREMISES

     A.   Landlord will tender and Tenant agrees to accept the Leased Premise in
          an "as is" condition; provided, however, Landlord shall contribute a
          sum not to exceed Fifteen & 00/100 Dollars ($15.00) per square foot of
          Rentable Area (the "Construction Allowance") toward the cost of
          supplying the installing permanent leasehold improvements in the
          Leased Premises in accordance with the Project Schedule Agreement
          attached hereto as Exhibit "D".  Any costs in excess of this amount
          shall be borne by Tenant.  Payment shall be made directly to
          Landlord's contractor performing said work.

     B.   Landlord shall contribute up to One and 00/100 Dollars ($1.00) per
          square foot of Rentable Area toward the cost of Tenant's designated
          architect providing space planning services and complete construction
          drawings for all leasehold improvements, including mechanical,
          electrical and plumbing (MEP) drawings to be prepared by Landlord's
          designated engineering firm.  Any costs in excess of the above amount
          shall be borne by Tenant.

23.  MOVING ALLOWANCE

     Landlord shall contribute up to One & 50/100 Dollars ($1.50) per square
foot of Rentable Area toward the moving costs incurred by Tenant, including,
without limitation, the costs of relocating Tenant's furniture, equipment and
telephones to the Leased Premises.  Such reimbursement shall be made thirty (30)
days after occupancy and receipt of an invoice from Tenant.

24.  PARKING

     A.   For each 1,000 square feet of Rentable Area leased and occupied in the
          Leased Premises, Landlord shall make available to Tenant up to three
          and one-half (3.5) unreserved parking permits in the Parking Garage in
          areas designated by Landlord, which shall be equally prorated through
          the Parking Garage unless otherwise directed by Landlord.  Landlord
          shall use good faith, reasonable efforts (subject to availability), to
          provide up to an additional one-half (0.5) unreserved parking permit
          per each 1,000 square feet of Rentable Area ("Additional Permits")
          leased and occupied on a month-to-month basis with Landlord retaining
          the right to recapture said Additional Permits upon thirty (30) days
          prior written notice.  Such Additional Permits may, at Landlord's
          election, be located in the Parking Garage, the One Greenway Garage,
          the Greenway East Garage, the Houston City Club Garage, the North
          Richmond Garage or in other garages or parking areas (within one (1)
          mile of the Project) Landlord may contract for Tenant's use.  During
          the initial term of the Lease, the charge for said parking permits
          shall be $16.50 per permit per month, plus state and local taxes.
          During

                                      -23-
<PAGE>

          the Renewal Period, the charge for said parking permits shall be at
          the then prevailing "market" rate, plus state and local taxes.

     B.   Landlord shall provide for a Tenant validation system for visitor
          parking.  All charges incurred during the first two (2) hours per
          visitor shall be free.  Tenant shall be liable for any additional
          charges incurred.

     C.   The driver of each car shall have so-called "in-and-out" privileges.
          Landlord shall not be responsible for any loss or damage to any car or
          property therein or for personal injury or death occurring in the
          parking area or garage, except to the extent caused solely by its own
          negligence or that of its own agents or employees in the scope of
          their employment.

25.  EXPANSION OPTION

     A.   Provided no uncured Event of Default has occurred under this Lease,
          Tenant shall have the option (the "Expansion Option") to lease
          approximately 4,386 square feet of Rentable Area (+/- 20%), on the
          sixth (6th) floor of the Building, as outlined and hatched on Exhibit
          "B" attached (the "Expansion Space"), at the "Fair Market Rental Rate"
          (as hereinafter defined).  In order to exercise such Expansion Option,
          Tenant shall be required to give Landlord written notice thereof
          ("Expansion Notice") no earlier than September 1, 1997 nor later than
          October 31, 1997.  However, Landlord shall have the option to tender
          possession of the Expansion Space to Tenant on any date between
          January 1 and August 31, 1998.

     B.   In the event Tenant leases space under this Paragraph 25, Tenant's
          Cancellation Option(s) as provided in Paragraph 28.A and Paragraph
          28.B shall be adjusted to take into consideration the increased Base
          Rental and amortization of Contributions provided by Landlord, if any,
          for the Expansion Space.

26.  PREFERENTIAL RIGHT TO LEASE

     A.   First Preferential Right to Lease Space

          (1)  Tenant shall have a Preferential Right to Lease approximately
               2,482 square feet of Rentable Area (+/- 20%) contiguous to the
               Leased Premises on the sixth (6th) floor of the Building (the
               "First Preferential Space"), as outlined and hatched on Exhibit
               "B" attached, which becomes available for direct lease to a new
               tenant (whether or not a bona fide offer has been made) prior to
               November 1, 1988; provided that (i) no Event of Default has
               occurred and is continuing, and (ii) Tenant remains in occupancy
               of the entire Leased Premises.

                                      -24-
<PAGE>

          (2)  At any time after the First Preferential Space becomes available,
               as provided above, but prior to leasing such space to a new
               tenant, Landlord shall first offer such space in writing to
               Tenant. Such offer notice shall specify the amount and location
               of such space, the date of availability, and shall be leased
               pursuant to the following provisions:

               (a)  The rental rate for the First Preferential Space shall be
                    the rental rate then in effect for the Leased Premises
                    (subject to increased and at such times as provided in
                    Paragraph 3 herein); and

               (b)  Landlord shall contribute a construction and architectural
                    allowance based upon the number of months remaining in the
                    initial term of the Lease from the commencement date of the
                    First Preferential Space multiplied by eighteen cents
                    ($0.18).

          (3)  Any First Preferential Space shall be leased for the period
               commencing upon the earlier of Tenant's possession of the First
               Preferential Space or the date of availability specified in
               Landlord's offer and expiring upn the last day of the term of the
               Lease, including the Renewal Period, if exercised. Rent shall
               commence on the earlier of (i) occupancy of the First
               Preferential Space by Tenant; (ii) Substantial Completion of the
               First Preferential Space; or (iii) forty-five (45) days from
               tender of possession of the First Preferential Space. Tenant
               shall have five (5) working days from receipt within which to
               accept or reject such offer. If Tenant rejects such offer or
               fails to accept such offer within the foregoing five (5) working
               day period, this First Preferential Right to Lease shall be
               deemed waived by Tenant for ninety (90) days during which time
               Landlord may lease all or a portion of the First Preferential
               Space. If a lease with another tenant(s) is not executed within
               said ninety (90) days period following Tenant's rejection or
               failure to notify period as provided above, then Tenant's
               Preferential Right to Lease with respect to such space shall be
               reinstated in full force and effect.

          (4)  If Tenant accepts Landlord's offer, Tenant shall, no later than
               twenty (20) days after Landlord's submission of such offer,
               execute an amendment of the Lease adding the First Preferential
               Space to the Leased Premises on the terms specified in Paragraph
               26.A(2), above.

          (5)  In the event Tenant leases space under this Paragraph 26.A,
               Tenant's Cancellation Option(s) as provided in Paragraph 28.A and
               Paragraph 28.B shall be adjusted to take into consideration the
               increased Based Rental and amortization of Contributions provided
               by Landlord, if any, for the First Preferential Space.

                                      -25-
<PAGE>

     B.   Second Preferential Right to Lease Space

          (1)  In the event Tenant has leased all space pursuant to its First
               Preferential Right to Lease Space hereinabove, Tenant shall have
               a Second Preferential Right to Lease approximately 5,616 square
               feet of Rentable Area (+/- 20%) contiguous to the Leased Premises
               on the sixth (6th) floor of the Building (the "Second
               Preferential Space"), as outlined and hatched on Exhibit "B"
               attached, which becomes available for direct lease to a new
               tenant (whether or not a bona fide offer has been made) prior to
               November 1, 1999; provided that (i) no Event of Default has
               occurred and is continuing; and (ii) Tenant remains in occupancy
               of the entire Leased Premises.

          (2)  At any time after the Second Preferential Space becomes
               available, as provided above, but prior to leasing such space to
               a new tenant, Landlord shall first offer such space in writing to
               Tenant.  Such offer notice shall specify the amount and location
               of such space, the date of availability and the Fair Market
               Rental Rate for such space.  Any Second Preferential Space shall
               be leased for the period commencing upon the earlier of Tenant's
               possession of the Second Preferential Space or the date of
               availability specified in Landlord's offer and shall be leased
               for a minimum of sixty (60) months from the commencement date of
               the Second Preferential Space.  Rent shall commence on the
               earlier of (i) occupancy of the Second Preferential Space by
               Tenant; (ii) Substantial Completion of the Second Preferential
               Space or (iii) forty-five (45) days from tender of possession of
               the Second Preferential Space.  Tenant shall have five (5)
               working days from receipt within which to accept or reject such
               offer.  If Tenant rejects such offer or fails to accept such
               offer within the foregoing five (5) working day period, this
               Second Preferential Right to Lease shall be deemed waived by
               Tenant for ninety (90) days during which time Landlord may lease
               all or a potion of the Second Preferential Space.  If a lease
               with another tenant(s) is not executed within said ninety (90)
               day period following Tenant's rejection or failure to notify
               period as provided above, then Tenant's Second Preferential Right
               to Lease with respect to such space shall be reinstated in full
               force and effect.

          (3)  If Tenant accepts Landlord's offer, Tenant shall, no later than
               twenty (20) days after Landlord's submission of such offer,
               execute an amendment of the Lease adding to the Second
               Preferential Space to the Leased Premises on the terms specified
               in Landlord's offer and extending the term (if necessary) of the
               Lease for the entire Leased Premises by the number of months to
               be coterminous with the Second Preferential Space term specified
               above.  The Base Rental for the Leased Premises shall continue

                                      -26-
<PAGE>

               during the remainder of the original term of the Lease at the
               rate(s) in effect under this Lease; thereafter, the rental rate
               for such space shall be at the Fair Market Rental Rate then in
               effect.

          (4)  In the event Tenant leases space under this Paragraph 26.B,
               Tenant's Cancellation Option(s) as provided in Paragraph 28.A and
               Paragraph 28.B shall be adjusted to take into consideration the
               increased Base Rental and amortization of Contributions provided
               by Landlord, if any, for the Second Preferential Space.

27.  FAIR MARKET RENTAL RATE

     A.   First Cancellation Option

          (1)  Upon not less than six (6) month's prior written notice to
               Landlord given at anytime prior to the end of the forty-second
               (42nd) full calendar month following the commencement of Tenant's
               Lease and occupancy of the original Leased Premises, the
               Expansion Space, the First Preferential Space, and the Second
               Preferential Space, as applicable, Tenant shall have the right to
               cancel this Lease with respect to all or a portion of the Leased
               Premises located on the sixth (6th) floor of the Building,
               subject to Tenant's payment of Stipulated Damages calculated
               pursuant to Subparagraph 28.A(2) below and the conditions in
               Subparagraph 28.A(3).

          (2)  Stipulated Damages shall be due and payable simultaneous with
               Tenant's written notice of intent to cancel under the provisions
               of this Paragraph 28.A or Tenant's cancellation rights shall be
               null and void.  If Tenant exercises its First Cancellation Option
               pursuant to this Paragraph 28.A, Tenant shall pay Landlord, as
               "Stipulated Damages", the sum of the following:

               (a)  The unamortized portion of Landlord's contributions, rental
                    abatement, moving allowance, and any other reimbursement
                    (collectively "Contributions") applicable to the Leased
                    Premises.  Any costs associated with asbestos abatement in
                    the Leased Premises shall not be included in Contributions.
                    For purposes of calculating Stipulated Damages,
                    Contributions shall be treated as if such were a loan, fully
                    amortized over the original term of the Lease at twelve
                    percent (12%) annual interest, compounded monthly.
                    Stipulated Damages as outlined herein are subject to
                    adjustment for any Expansion Space and/or Preferential Right
                    Space leased by Tenant pursuant to Paragraph 25 and
                    Paragraph 26.  Amortization of Contributions attributable to
                    the Expansion

                                      -27-
<PAGE>

                    Space shall begin upon the commencement date of the
                    respective additional space leased; plus

               (b)  An amount equal to three (3) month's Base Rental based on
                    the Base Rental being paid by Tenant at the time of said
                    cancellation.

          (3)  Tenant's First Cancellation Option shall be subject to the
               condition that (i) an Event of Default shall not have occurred
               and is continuing at the time of exercise, (ii) Tenant is in
               occupancy of the entire Leased Premises prior to Tenant's written
               notice, (iii) Landlord is unable to accommodate Tenant's growth
               by providing additional premises containing no less than fifty
               percent (50%) of the then current Rentable Area of the Leased
               Premises in one (1) contiguous space to be located in either One,
               Two, Eight or Twelve Greenway Plaza or 8800 Buffalo Speedway;
               (iv) Tenant has leased and occupied the original Leased Premises,
               the Expansion Space, the First Preferential Space and the Second
               Preferential Space, in accordance with this Lease; and (v) Tenant
               has leased and occupied that portion of the leased Premises being
               cancelled for a minimum of forty-two (42) months.  Therefore the
               Lease and/or any amendment(s) thereto may be terminated
               separately depending on the commencement date of the original
               Leased Premises, the Expansion Space, the First Preferential
               Space, and the Second Preferential Space, as the case may be,
               relative to the forty-two (42) month minimum term provided
               herein.  If Tenant exercises its First Cancellation Option with
               respect to any portion of the Leased Premise, Tenant at its sole
               cost and expense, shall be responsible for the installation of a
               demising partition separating that portion of the Leased Premises
               being canceled from any remaining portion of the Leased Premises
               not so canceled.  Moreover, at all times following the giving of
               such notice and prior to the effective date of cancellation of
               this Lease with respect to the applicable portion(s) of the
               Leased Premises, Tenant shall be bound by and obligated to comply
               with the covenants, duties and obligations of Tenant under this
               Lease, including without limitation the payment of Base Rental
               and all other sums due and payable by Tenant hereunder.

          (4)  If Tenant exercises its First Cancellation Option with respect to
               any portion of the Leased Premises, any option(s) for additional
               space outstanding at the time of said cancellation shall become
               null and void.

     B.   Second Cancellation Option

          (1)  Effective April 30, 2000, Tenant shall have the right to cancel
               this Lease with respect to the entirety of the Leased Premises
               located on the sixth

                                      -28-
<PAGE>

               (6th) floor of the Building, subject to Tenant's payment of
               Stipulated Damages calculated pursuant to Subparagraph 28.B(2)
               below. Tenant must give Landlord written notice of its intent to
               exercise this option and on or before July 31, 1999.

          (2)  Stipulated Damages shall be due and payable simultaneous with
               Tenant's written notice of intent to cancel under the provisions
               of this Paragraph 28.B or Tenant's cancellation rights shall be
               null and void.  If Tenant exercises its Second Cancellation
               Option pursuant to this Paragraph 28.B, Tenant shall pay
               Landlord, as "Stipulated Damages", the sum of the following:

               (a)  The unamortized portion of Landlord's contributions, rental
                    abatement, moving allowance, and any other reimbursement
                    (collectively "Contributions") applicable to the Leased
                    Premises.  The costs of any asbestos abatement shall be
                    excluded from the calculation of the Contributions.  For
                    purposes of calculating Stipulated Damages, Contributions
                    shall be treated as if such were a loan, fully amortized
                    over the original term of the Lease at twelve percent (12%)
                    annual interest, compounded monthly.  Stipulated Damages as
                    outlined herein are subject to adjustment for any Expansion
                    Space and/or Preferential Right Space leased by Tenant
                    pursuant to Paragraph 25 and Paragraph 26.  Amortization of
                    Contributions attributable to the Expansion Space, the First
                    Preferential Space and/or Second Preferential Space shall
                    begin upon the commencement of the respective additional
                    space leased; plus

               (b)  An amount equal to one (1) month's Base Rental based on the
                    Base Rental being paid by Tenant at the time of said
                    cancellation.

          (3)  Tenant's Second Cancellation Option under this Paragraph 28.B
               shall be subject to the condition that (i) an Event of Default
               shall not have occurred at the time of exercise and is
               continuing, (ii) Tenant relocates its corporate offices outside
               of the state of Texas; and (iii) Tenant has occupied the original
               Leased Premises, the Expansion Space, the First Preferential
               Space, the Second Preferential Space, or any expansion thereof
               each for a minimum of forty-two (42) months.  Therefore, the
               Lease and/or any amendment(s) thereto may be terminated
               separately depending on the commencement date of the original
               Leased Premises, the Expansion Space, the First Preferential
               Space, or the Second Preferential Space, as the case may be,
               relative to the forty-two (42) month minimum term provided
               herein.  If Tenant exercises its Second Cancellation Option with

                                      -29-
<PAGE>

               respect to any portion of the Leased Premises, Tenant, at its
               sole cost and expense, shall be responsible for the installation
               of a demising partition separating that portion of the Leased
               Premises being canceled from any remaining portion of the Leased
               Premises not so canceled.  Moreover, at all times following the
               giving f such notice and prior to the effective date of
               cancellation of this Lease with respect to the applicable
               portion(s) of the Leased Premises, Tenant shall be bound by and
               obligated to comply with the covenants, duties and obligations of
               Tenant under this Lease, including without limitation the payment
               of Base Rental and all other sums due and payable by Tenant
               hereunder.

          (4)  If Tenant exercises its Second Cancellation Option with respect
               to any portion of the Leased Premises, any option(s) for
               additional space outstanding at the time of said cancellation
               shall become null and void.

29.  RENEWAL OPTION

     Provided that Tenant (i) shall not at such time be in default of any of the
terms or provisions of the Lease; (ii) shall be in occupancy of the entire
Leased Premises; and (iii) subject to any existing preferential rights to lease,
renewal options, or rights of refusal; Tenant shall have an option (the "Renewal
Option") to renew the Lease for one (1) additional five (5) year period (the
"Renewal Period"), commencing on the first day following expiration of the
initial term of the Lease, except that the rental rate shall be at the Fair
Market Rental Rate.  In order to exercise such Renewal Option, Tenant shall give
written preliminary notice thereof no earlier than thirteen (13) months nor
later than twelve (12) months prior to the end of the initial term of the Lease.
Within fifteen (15) days after the preliminary notice, Landlord shall advise
Tenant in writing f the Fair Market Rental Rate applicable during the Renewal
Period.  Within thirty (30) days after Tenant has received such rental
information from Landlord, Tenant shall give Landlord written notice of the
exercise of its Renewal Option.  Failure of Tenant to give such notice within
such thirty (30) days period shall cause such Renewal Option to be void and of
no further force and effect.  If Tenant exercises this Renewal Option, the First
Cancellation Option provided in Paragraph 28.A above shall be null and void.

30.  HOUSTON CITY CLUB

     Landlord agrees to pay, out of the Base Rent payable for the first (1st)
month of the term of this Lease for which Base Rent is due, on behalf of Tenant,
the initiation fees in connection with three (3) Athletic Memberships to the
Houston City Club.  Such memberships shall be activated on the Commencement Date
(or as soon thereafter as practicable), subject to the prior approval of The
Houston City Club.

31.  HAZARDOUS MATERIAL; INDEMNITY

                                      -30-
<PAGE>

     A.   Tenant shall not cause or permit any Hazardous Material (as
          hereinafter defined) to be brought upon, kept or used in or about the
          Leased Premises or the Project by Tenant or its agents, employees,
          contractors or invitees without the prior written consent of Landlord
          (which Landlord shall not unreasonably withhold as long as Tenant
          demonstrates to Landlord's reasonable satisfaction that such Hazardous
          Material is necessary or useful to Tenant's business and will be used,
          kept and stored in a manner that complies with all laws regulating any
          such Hazardous Material so brought upon or used or kept in or about
          the Leased Premises or the Project).  If Tenant breaches the
          obligations stated in the preceding sentence, or if the presence of
          Hazardous Material on the Leased Premises or the Project caused or
          permitted by Tenant results in contamination of the Leased Premises or
          the Project, or if contamination of the Leased Premises or the Project
          by Hazardous Material otherwise occurs for which Tenant is legally
          liable to Landlord for damage resulting therefrom, then Tenant shall
          indemnify, defend and hold Landlord harmless from any and all claims,
          judgments, damages, penalties, fines, costs, liabilities or losses,
          including, without limitation, diminution in value of the Leased
          Premises, damages, penalties, fines, costs, liabilities or losses
          (including, without limitation, restriction on use of rentable or
          usable space or of any amenity of the Leased Premises or the Project
          [line missing] damages arising from any adverse impact on marketing of
          space, and sums paid in settlement of claims, attorney's fees and
          expert fees) which arise during or after the term of the Lease as a
          result of such contamination.  This indemnification of Landlord by
          Tenant includes, without limitation, costs incurred in connection with
          any investigation of site conditions or any clean up, remedial,
          removal or restoration work required by any federal, state or local
          governmental agency or political subdivision because of Hazardous
          Material present in the soil or ground water on or under the Leased
          Premises or the Project.  Without limiting the foregoing, if the
          presence of any Hazardous Material on the Premises or the Project
          caused or permitted by Tenant results in any contamination of the
          Leased Premises or the Project, Tenant shall promptly take all actions
          at its sole expense as are necessary to return the Leased Premises and
          the Project to the condition existing prior to the introduction of any
          such Hazardous Material to the Leased Premises or the Project;
          provided that Landlord's approval of such actions shall first be
          obtained, which approval shall not be unreasonably withheld so long as
          such actions would not potentially have any material adverse long-term
          or short-term effect on the Leased Premises or the Project.  The
          indemnification of Landlord by Tenant contained in this Paragraph 30
          shall survive the expiration or earlier termination of this Lease.

     B.   As used herein, the term "Hazardous Material" means any hazardous or
          toxic substance, material or waste which is or becomes regulated by
          any local governmental authority, the State of Texas or the United
          States Government, including, but not limited to, any material or
          substance that is (i) petroleum, (ii) asbestos, (iii) designated as a
          "hazardous substance" pursuant to Section 311

                                      -31-
<PAGE>

          of the Water Pollution Control Act (33 U.S.C. Section 1321), (iv)
          designated as a "hazardous waste" pursuant to Section 1004 of the
          Resource Conversation and Recovery Act, 42 U.S.C. Section 6901, (v)
          defined as a "Hazardous substance" pursuant to Section 101 of the
          Comprehensive Environmental Response, Compensation and Liability Act,
          42 U.S.C. Section 9601, or (vi) defined as a "regulated substance"
          pursuant to Subchapter IX, Solid Waste Disposal Act, 42 U.S.C. Section
          6991.

     C.   Landlord advises Tenant that, per the building inspection performed by
          Law Engineers in 1985 and McClelland Management Services in 1990, the
          following materials in Two Greenway Plaza were found to contain
          asbestos in amounts greater than one percent (1%): (i) sprayed-on
          fireproofing applied to the concrete structure throughout most of the
          Building; (ii) cementitious white mud insulation on the heat exchanger
          tanks in the basement mechanical room; (iii) pipe fitting and pipe run
          insulation (thin white mud-mastic type) on hot and chilled water lines
          throughout the Building mechanical rooms; (iv) tar coated pipe fitting
          insulation and pipe run insulation (black tar) on the chilled and hot
          water lines through the Building mechanical rooms; (v) cementitious
          white mud insulation on the condensate drain line in the Building
          mechanical rooms; and (vi) tar coating n duct insulation in the
          basement mechanical room.  The materials noted in (i) through (vi)
          above have been removed from floors one through five, seven through
          eleven and a portion of six of the Building.  If Tenant leases
          additional space pursuant to any option or preferential right
          contained in this Lease and said additional space contains asbestos,
          Landlord, at its sole cost and expense, will cause to have said
          asbestos removed.

32.  MISCELLANEOUS

     A.   Provided Tenant complies with its covenants, duties and obligations
          hereunder, Tenant shall quietly have, hold and enjoy the Leased
          Premises subject to the terms and provisions of this Lease.

     B.   In any circumstance where Landlord or Landlord's Mortgagee (or their
          agents or employees) are permitted to enter the Leased Premises, no
          such entry shall constitute an eviction or disturbance of Tenant's use
          and possession of the Leased Premises; be a breach by Landlord of any
          of its obligations; render Landlord liable for damages; entitle Tenant
          to be relieved from any of its obligations; nor grant Tenant any right
          of setoff, recoupment or other remedy.  In connection with any such
          entry incident to performance of repairs, replacement, maintenance or
          construction, all of the aforesaid provisions shall be applicable
          notwithstanding that Landlord may elect to take building materials in,
          to or upon the Leased Premises.

                                      -32-
<PAGE>

     C.   Tenant will not assert any claim or counterclaim against Landlord of
          whatever nature or description in any legal proceeding unless during
          the pendency of the proceeding Tenant pays to Landlord or into the
          registry of the court all rent as it becomes due under this Lease.

     D.   The remedies of Landlord shall be cumulative; whether exercised by
          Landlord or not shall be deemed to be in [line illegible] otherwise
          provided in this Lease, granting of consent is within the sole
          discretion of the party whose consent is required and withholding of
          such consent need not be reasonable or based on good cause.

     E.   Where Tenant is required to pay any sum or do any act at a particular
          time or within an indicated period, it is understood that time is of
          the essence.

     F.   The obligation of Tenants to pay all rent and other sums provided
          under this Lease to be paid by Tenant and the obligation of Tenant to
          perform Tenant's other covenants and duties under this Lease
          constitute independent, unconditional obligations to be performed at
          all times provided for under this Lease, save and except only when an
          abatement, reduction or offset right is expressly provided in this
          Lease, and not otherwise.  Tenant waives any right to assert, as
          either a claim or defense, that Landlord is obligated to perform or is
          liable for the nonperformance of any implied covenant or implied duty
          of Landlord not expressly set forth in this Lease.  Tenant waives any
          implied warranty by Landlord that the Leased Premises are suitable for
          their intended commercial purposes; provided that such waiver shall
          not relieve Landlord of its express obligations under this Lease,
          specifically including without limitation its obligations regarding
          construction and maintenance and repair of the Leased Premises.  Other
          than as expressly set forth in this Lease, Landlord makes no express
          warranty nor shall there be any implied warranty regarding the
          condition of the Leased Premises.  Tenant agrees to perform all of its
          obligations hereunder (including, without limitation, the obligation
          to pay rent), irrespective of any breach or alleged breach by Landlord
          of any such implied warranty; provided that Tenant shall have the
          right to bring an action for injunction or for damages caused by such
          breach.  Tenant agrees that Landlord shall incur no liability to
          Tenant by reason of any defect in the Leased Premises, whether
          apparent or latent.  Tenant waives and relinquishes all rights which
          Tenant might have to claim any nature of lien against any rent or
          other sums payable by Tenant under this Lease.  Notwithstanding the
          foregoing, Landlord's contractor will warrant the workmanship of the
          construction performed within the Leased Premises for a one (1) year
          period from Substantial Completion ("Contractor Warranty").  Landlord
          will use good faith efforts to enforce said Contractor Warranty.

                                      -33-
<PAGE>

     G.   Under no circumstances whatsoever shall Landlord or Tenant ever be
          liable for consequential damages or special damages.  Tenant waives
          and relinquishes all rights which Tenant may have to claim any kind of
          prejudgment lien against rent owed Landlord or against Landlord's
          property.

     H.   All monetary obligations of Landlord and Tenant (including, without
          limitation, any monetary obligation of Landlord or Tenant for damages
          for any breach of their respective covenants, duties or obligations)
          are performable exclusively in Houston, Harris County, Texas.

     I.   If any provision of this Lease shall ever be held to be invalid or
          unenforceable, such invalidity or unenforceability shall not affect
          any other provision of the Lease, but such other provisions shall
          continue in full force and effect.

     J.   The term "Landlord" shall mean only the owner, for the time being, of
          the Building.  Landlord reserves the right to transfer, assign or
          convey, in whole or in part, the building, the Land, the Project, any
          interest in any of the foregoing and its interest in this Lease.  In
          the event of the transfer by such owner of its interest in the
          Project, Building or this Lease, such owner shall thereupon be
          released and discharged from all covenants and obligations of the
          Landlord thereafter accruing; but such covenants and obligations shall
          be binding during the Lease term upon each new owner of the Project or
          Building (or assignee of the Landlord's interest under this Lease) for
          the duration of such owner's ownership.  All liability of Landlord for
          damages for breach of any covenant, duty or obligation of Landlord
          hereunder shall be satisfied only out of the interest of Landlord in
          the Building existing at the time any such liability is adjudicated in
          a proceeding as to which the judgment adjudicating such liability is
          nonappealable and not subject to further review.

     K.   Tenant represents and warrants that it has not been represented by any
          broker or agent in connection with the negotiation or execution of
          this Lease, except for Lewis Partners, Inc.  Tenant shall indemnify
          and hold harmless Landlord and Landlord's designated property
          management firm from and against all claims (including costs of
          defending against and investigating such claims) of any broker or
          agent or similar party claiming by, through or under Tenant in
          connection with this Lease.

     L.   Whenever either party is required to pay for attorneys' fees,
          realtors' commissions or other professional fees and expenses on
          behalf of the other party, such fees and commissions shall be
          commercially reasonable.

33.  ENTIRE AGREEMENT AND BINDING EFFECT

                                      -34-
<PAGE>

     This Lease and any attached exhibits signed or initialed by the parties
constitute the entire agreement between Landlord and Tenant.  No prior written
or prior or contemporaneous oral promises or representations shall be binding.
This Lease shall not be amended, except by written instrument signed by Landlord
and Tenant; no agent or employee of Landlord or Tenant has authority to modify
this Lease.  Paragraph captions are for convenience only, and neither limit nor
amplify the provisions of this Lease.  The provisions of this Lease shall be
binding upon and inure to the benefit of the heirs, executors, administrators,
successors and assigns of the parties, but this provision shall in no way alter
the restriction herein in connection with assignment and subletting by Tenant.
The submission of this Lease by Landlord for examination does not constitute a
reservation of or option for the Leased Premises.  This Lease shall become
effective only upon execution by all parties and delivery by Landlord to Tenant.

                                      -35-
<PAGE>

     EXECUTED by the parties on the respective dates stated below, the later of
which constituting Effective Date of this Lease.

                         GREENWAY PLAZA, LTD., by its managing partner, J/K-G/P
                         #1, LTD., but its sole general partner, J/K Holdings,
                         Inc.

                         By: /s/ Neil Tofsky
                             ---------------------------------------
                         Neil Tofsky, Senior Vice President

                         LANDLORD

                         Date: October 2, 1996
                               -------------------------------------

                         PHYSIX, INC., a Texas corporation


                         By: /s/ Tom Giannulli
                             ---------------------------------------
                         Name: Tom Giannulli
                               -------------------------------------
                         Title: President/CEO
                                ------------------------------------

                         Date: 9/27/96
                               -------------------------------------

                         TENANT

                                      -36-