<PAGE>

                                                                   EXHIBIT 10.15

                                   SUBLEASE

THIS SUBLEASE is executed by and between Trilogy Software, Inc. ("Trilogy"), a
Delaware corporation, and pcOrder.com, Inc. ("pcOrder"), a Delaware corporation,
to be effective as of June 1, 1999.

                                    RECITALS

Reference is made to that certain Office Lease (the "Master Lease") executed by
and between Trilogy, as "Lessee," and Opus South Corporation, as "Lessor,"
whereby Trilogy leased from Landlord a three story commercial office building,
containing approximately  122,530 rentable square feet of space, located in
Austin, Travis County, Texas, commonly known as Plaza on the Lake II. A true and
correct copy of the Master Lease is attached as Exhibit A hereto and
incorporated herein by reference. Opus South Corporation, together with its
successors in interest as "Lessor" under  the Master Lease, is hereafter
referred to as "Landlord." Unless otherwise defined herein, terms used herein
which are defined in the Master Lease shall be given the same meanings herein as
are ascribed to them in the Master Lease.

Trilogy has agreed to sublease a portion of the Premises to pcOrder, pcOrder has
agreed to sublease a portion of the Premises from Trilogy, all on the terms and
conditions set forth herein.

                                   AGREEMENTS

NOW, THEREFORE, for and in consideration of the mutual covenants and agreements
set forth herein, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, Trilogy and pcOrder hereby agree as
follows:

1)  Demise and Description of Property

Trilogy hereby leases to pcOrder, and pcOrder hereby leases from Trilogy,
approximately 38,560 rentable square feet of space on the first floor of the
Office Complex (the "Subleased Premises") as reflected on Exhibit B attached
hereto and incorporated herein by reference.

2)  Term

This Sublease is for a term of approximately 70 months (the "Sublease Term"),
beginning on June 1, 1999 (the "Commencement Date"), and ending on April 7, 2005
(the "Termination Date"). But this Sublease will terminate earlier in the event
of a surrender, forfeiture, or termination of the Master Lease. If the Master
Lease shall expire or terminate prior to the Termination Date, (1) a termination
of this Sublease will be simultaneously effected, (2) the rental paid or to be
paid under this Sublease shall abate proportionately, (3) any rentals paid to
Trilogy for a period beyond such termination shall be repaid to pcOrder, and (4)
all amounts owed by pcOrder this Sublease shall be immediately due and payable
to Trilogy. In the event Trilogy receives any type of notice from the Lessor
under the Master Lease which would directly affect pcOrder and its rights under
this Sublease, then Trilogy will forward a copy of such notice to pcOrder with
five business days of receipt.

3)  Base Rent

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pcOrder hereby covenants and agrees to pay Trilogy, at Trilogy's principal
office at the address set forth  below, monthly rent (the "Base Rent") for the
Subleased Premises as follows:


               Months                          Base Rent
-----------------------------------   ------------------------
1 through 11 inclusive                  $62,720.04
-----------------------------------   ------------------------
12 through 47 inclusive                 $64,328.25
-----------------------------------   ------------------------
48 through 71 inclusive                 $69,152.87
-----------------------------------   ------------------------

The Base Rent shall be payable in advance, in equal monthly installments,
commencing on the Commencement Date and continuing on the first day of each
calendar month thereafter for the balance of the Sublease Term. If the
Commencement Date is a date other than the first day of a calendar month, then
the Base Rent for such calendar month shall be prorated accordingly.

4)  Additional Rent

pcOrder shall pay to Trilogy, as Additional Rent under this Sublease, pcOrder's
"Proportionate Share" (defined as 31.5%) of all amounts which become due and
payable by Trilogy as Additional Rent under the Master Lease. pcOrder's
Proportionate Share of the Additional Rent shall be paid in the same manner, and
at the same time, as the Additional Rent payments under the Master Lease.

5)  Common Areas

The "Common Area" is that part of the Office Complex designated by Trilogy or
Landlord, from time to time, for the common use, benefit, and enjoyment of all
tenants and guests, including, among other facilities, parking area, sidewalks,
landscaping, curbs, loading areas, private streets and alleys, lighting
facilities, hallways, malls, atria, rest rooms, and other areas and improvements
provided in the Office Complex for the common use and enjoyment of all tenants,
all of which shall be subject to Trilogy's sole management and control and shall
be operated and maintained in such manner as Trilogy, in its discretion, shall
determine.  pcOrder and its employees, customers, subtenants, licensees, and
concessionaires shall have the non-exclusive right and license to use the Common
Area, as constituted from time to time, such use to be in common with Trilogy,
any other tenants of the Office Complex, and other persons permitted by Trilogy
or Landlord to use the same. This non-exclusive right and license shall include
the right to utilize a proportionate share of the parking places available under
the Master Lease. The non-exclusive right and license to use the Common Area, as
constituted from time to time, shall be subject to the Building Rules and
Regulations, and such other reasonable rules and regulations governing the use
thereof as Trilogy or Landlord may, from time to time, prescribe, including the
designation of specific areas within the Office Complex or in reasonable
proximity thereto in which automobiles owned by Tenants, its employees,
subtenants, licensees and concessionaires shall be parked. Trilogy and/or
Landlord shall at all times have the right to change such rules and regulations
or to promulgate other rules and regulations in such manner as may be deemed
advisable for safety, care or cleanliness of the Office Complex and for
preservation of good order therein, all of which rules and regulations, changes
and amendments will be forwarded to

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pcOrder in writing and shall be carried out and observed by pcOrder. pcOrder
shall further be responsible for the compliance with such rules and regulations
by the employees, servants, agents, visitors and invitees of pcOrder. Trilogy or
Landlord may temporarily close any part of the Common Area for such periods of
time as may be necessary to prevent the public from obtaining prescriptive
rights or to make repairs or alterations.

6)  Condition of Subleased Premises

pcOrder acknowledges that Landlord has completed construction of the
improvements to the Subleased Premises required under Article 1 of the Master
Lease. pcOrder  has had an opportunity to inspect the Subleased Premises and has
found it satisfactory for pcOrder's intended use. Accordingly, pcOrder accepts
the Subleased Premises in their "AS-IS" condition and Trilogy shall have no
obligation to improve, repair, restore, or refurbish the Subleased Premises.
pcOrder acknowledges that neither Trilogy, nor any agent of Trilogy, has made
any representation or warranty with respect to the Subleased Premises or any
other portion of the Office Complex including, without limitation, any
representation or warranty with respect to the suitability or fitness of the
Subleased Premises or any other portion of the Office Complex for the conduct of
pcOrder's business. Subject to obtaining the prior approval of Landlord as
required by Article 7 of the Master Lease and Trilogy's approval, as hereafter
provided, pcOrder shall be entitled to make such alterations and improvements to
the Subleased Premises as pcOrder may determine are appropriate for pcOrder's
use of the Subleased Premises. Prior to undertaking any alterations of or
improvements to the Subleased Premises, pcOrder shall submit a written request
for approval to Trilogy, together with the plans and specifications for such
alterations and improvements.  Trilogy's approval shall not be unreasonably
withheld, delayed or denied.  If Landlord and Trilogy each gives its consent,
according to the requirements of this agreement, to alterations or improvements
to the Subleased Premises by pcOrder, pcOrder shall procure, at pcOrder's
expense, all necessary permits before undertaking such work.  All such
alterations shall be done at pcOrder's sole cost and expense, and in accordance
the provisions and requirements of the Master Lease and in accordance with all
applicable laws, including applicable building codes and regulations.

7)  Use of Subleased Premises

pcOrder will use the Subleased Premises only for office space and for uses
normally incident to that purpose.  Under no circumstances shall pcOrder utilize
the Subleased Premises, or allow the Subleased Premises to be utilized, in any
form or fashion which would violate any term, covenant, or condition of the
Master Lease or any applicable law, rule, regulation, or order governing the use
and enjoyment of the Subleased Premises.

8)  Assumption Agreement and Covenants

  a) pcOrder will comply with all of the provisions of the Master Lease that
     are to be performed by Trilogy as Tenant during the Sublease Term insofar
     as such provisions relate to the Subleased Premises and Tenant's use of
     Common Areas, but the rent provisions of the Master Lease will not apply to
     pcOrder. Paragraphs 3 and 4, above, govern pcOrder's payment of rent.

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  b) All of the terms and conditions contained in the Master Lease, to the
     extent that they do not conflict with specific provisions of this Sublease,
     are made a part of this Sublease, and the rights and obligations contained
     in the Master Lease are, during the term of this subletting, imposed on the
     respective parties, Trilogy being substituted for Landlord in the Master
     Lease, and pcOrder being substituted for Trilogy in the Master Lease.
     pcOrder recognizes that Trilogy is not in a position to independently
     render any of the services or to perform any of the obligations required of
     Trilogy by the terms of this Sublease. Therefore, notwithstanding anything
     to the contrary contained in this Sublease, pcOrder agrees that performance
     by Trilogy of all of its obligations under this Sublease (other than those
     set forth in Sections 8(c) and 9(c) below) is conditional upon the due
     performance by Landlord of its corresponding obligations under the Master
     Lease.

  c) Trilogy agrees to pay the Basic Rent, the Additional Rent, and all other
     sums which may become due and payable to Landlord under the Master Lease,
     as and when due, and to otherwise comply with all other terms and
     conditions of the Master Lease as to that part of the Premises not sublet
     to pcOrder. Trilogy further agrees to notify pcOrder immediately upon its
     receipt of any notice or other communication received from Landlord under
     or pertaining to the Master Lease which would potentially have a material
     impact upon pcOrder and/or this Sublease, including any notice of default
     or potential default under the Master Lease.  In the event Trilogy fails to
     cure any default by Trilogy under the Master Lease within any applicable
     cure periods, pcOrder shall have the right, but not the obligation, to cure
     such default, subject in any event to the willingness of the Lessor to
     accept such cure from pcOrder, and in such event Trilogy shall be obligated
     to reimburse pcOrder promptly for any reasonable costs incurred by pcOrder
     in effecting such cure.

9)   Limitation of Liability and Indemnity

  a) Notwithstanding any contrary provision of the Master Lease, neither the
     Landlord nor Trilogy will be liable to pcOrder, or any of its agents,
     employees, servants, or invitees, (nor will pcOrder be liable to Trilogy or
     any of its agents, employees, servants, or invitees), for any damage to
     persons or property due to the condition, design, or any defect in the
     Office Complex or its mechanical systems that may exist or subsequently
     occur. pcOrder, with respect to itself and its agents, employees, servants,
     and invitees, assumes all risks and damage to persons and property, either
     proximate or remote, by reason of the present or future condition of the
     Subleased Premises or the Office Complex. Trilogy, with respect to itself
     and its agents, employees, servants, and invitees, assumes all risks and
     damage to persons and property, either proximate or remote, by reason of
     the present or future condition of the Office Complex.

  b) Except for any claims, losses, costs, liabilities, actions, and damages
     that Trilogy has expressly released, or for which Trilogy's otherwise
     responsible as an occupant of the Office Complex, and except for those
     matters for which Trilogy is obligated to indemnify pcOrder pursuant to
     this Sublease, pcOrder agrees to indemnify, protect, defend, and hold
     Trilogy and Trilogy's partners, shareholders, employees, and agents
     harmless from

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     and against any and all claims, losses, costs, liabilities, actions, and
     damages, including, without limitation, reasonable attorney's fees and
     costs, incurred by or on behalf of any person or persons, firm or firms,
     corporation or corporations, arising from any breach or default on the part
     of pcOrder in the performance of any covenant or agreement on the part of
     pcOrder to be performed pursuant to the terms of this Sublease, or arising
     primarily from any act or negligence on the part of pcOrder or its agents,
     contractors, servants, employees, or licensees, or arising from any
     accident, injury, or damage, to the extent, and only to the extent, caused
     by pcOrder or its agents or employees, to any person, firm, or corporation
     occurring during the term of this Sublease or any renewal thereof, in or
     about the Subleased Premises and the Office Complex, and from an against
     all costs, reasonable counsel fees, expenses, and liabilities, incurred in
     connection with any such claim, action, or proceeding brought thereon; and
     in case any action or proceeding shall be brought against Trilogy by reason
     of any such claim, pcOrder, upon notice from Trilogy, covenants to resist
     and defend such action or proceeding by counsel reasonably satisfactory to
     Trilogy.

  c) Notwithstanding anything contained herein to the contrary, Trilogy shall be
     liable for, pcOrder shall not be liable for, and Trilogy shall indemnify,
     protect, defend, and hold pcOrder and its partners, shareholders,
     directors, and employees harmless from and against any and all liability
     caused, in whole or in part, by the act, neglect, fault, or omission of any
     duty by Trilogy, its agents, contractors, servants, employees, or
     licensees, whether in the Subleased Premises, the Office Complex, the
     Parking Garage, or the other parking areas.

10)  Insurance

Article 5 of the Master Lease details the insurance requirements imposed on
Trilogy. Section 9.3 of the Master Lease requires any sublessee under the Master
Lease to deliver certificates of insurance evidencing the issuance of insurance
policies in the forms and content required by Article 5. Upon request by
Trilogy, pcOrder will deliver certificates of insurance complying with the
requirements of Article 5 and Section 9.3 of the Master Lease to Landlord and
Trilogy. Upon request by Trilogy, each insurance policy required under Article 5
of the Master Lease which is to name Landlord as an additional insured shall
also name Trilogy as an additional insured. In addition and upon request by
Trilogy, each insurance policy required under Article 5 of the Master Lease
which is to contain a waiver of subrogation with respect to Landlord will also
contain a waiver of subrogation with respect to Trilogy.

11)  Taxes on pcOrder's Property

pcOrder shall pay, and indemnify, defend, and hold Trilogy and Landlord harmless
against, all taxes, impositions, and assessments, of every kind, levied or
assessed against personal property, furniture, fixtures, and other improvements
placed by or for pcOrder in the Subleased Premises.

12)  Renewal Option

Section 15.25 of the Master Lease provides Trilogy with the option to renew the
Master Lease for one (1) additional term of five (5) years. In the event Trilogy
elects to exercise its option to

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renew the Master Lease, Trilogy will provide pcOrder with the option of renewing
this Sublease for the same period. The option to renew this Sublease must be
exercised by written notice delivered by pcOrder to Trilogy at least three
hundred (300) days before the end of the Sublease Term. The Base Rent for the
renewal term of this Sublease shall be determined by taking the Base Rent which
is determined for the renewal term of the Master Lease and multiplying it by
pcOrder's Proportionate Share.

13)  Right of First Notice to Purchase

Section 15.27 of the Master Lease provides Trilogy with a "Right of First Notice
to Purchase" the Office Complex in the event Landlord determines that it wishes
to sell the Office Complex. This right of first notice with respect to the
purchase of the Office Complex is personal to Trilogy, and not assignable by
Trilogy. None of the rights, privileges or benefits afforded to Trilogy under
Section 15.27 of the Master Lease shall be exercisable or otherwise enjoyed by
pcOrder.  In the event Trilogy exercises such right, however, Trilogy agrees
that this Sublease shall become a direct lease between Trilogy and pcOrder on
the same terms and conditions.

14)  Signs

pcOrder covenants and agrees that no signs or symbols shall be placed in the
windows or doors of the Subleased Premises, or on any exterior part of the
Office Complex, without Trilogy's and the Landlord's prior written approval. Any
sign or symbol placed on the exterior of Office Complex or in the windows or
doors of the Office Complex so as to be visible from the street, that is not
satisfactory to Trilogy, shall be removed immediately on demand by Trilogy and
if not so removed within twenty-four (24) hours will constitute a breach of this
Sublease. pcOrder shall remove any approved sign placed on or about the exterior
of the Subleased Premises when this lease expires or terminates, and any damage
to the Office Complex or Subleased Premises resulting from the removal will be
repaired at pcOrder's sole cost and expense.

15)  Building Rules

pcOrder will comply with such rules and regulations generally applying to
tenants in the Building as may be adopted from time to time by Landlord and/or
Trilogy and delivered in writing to pcOrder for the management, safety, care and
cleanliness of, and the preservation of good order and protection of property in
the Subleased Premises and the Building. Trilogy hereby reserves all rights
necessary to implement and enforce such building rules and regulations.

16)  Access

pcOrder shall allow Landlord and Trilogy, and their agents, free access at all
reasonable times to the Subleased Premises for purposes of inspecting or making
repairs, additions, or alterations to the Subleased Premises or any property
owned by or under the control of Landlord or Trilogy.

17)  Furniture and Fixtures

All furniture, fixtures and equipment placed in the Subleased Premises by
pcOrder, including without limitation any computer or telecommunications systems
or equipment, will remain pcOrder's property, subject to Trilogy's rights as
provided by law. pcOrder may, when the

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Sublease Term expires, remove such furniture, fixtures and equipment if removal
is done so as not to damage the Subleased Premises; or if any damage does occur
such damage is repaired.


18)  Assignment and Subletting

     a) pcOrder will not assign or sublease the Subleased Premises, or any part
        of the Subleased Premises, without Trilogy's prior written consent,
        which may be withheld at Trilogy's discretion.

     b) Notwithstanding the foregoing, this Sublease may be assigned, or the
        Subleased Premises sublet, in whole or in part, to any corporation or
        other legal entity into which, or with which, pcOrder may be merged or
        consolidated or that acquires substantially all the assets of pcOrder or
        to any corporation or other legal entity that is a majority-owned
        subsidiary, parent, or affiliate of pcOrder.

     c) If there is an assignment, the assignee will agree in writing to assume
        all the terms and covenants of this Sublease to be performed by pcOrder.
        A duplicate original of that assignment and assumption agreement will be
        delivered to Trilogy within ten (10) days following the date of its
        execution or its effective date, whichever is earlier. pcOrder's
        liability under this Sublease, and that of any assignee of this
        Sublease, will survive any assignment or subletting, and such liability
        will be unaffected by any extension of time that Trilogy may grant to
        any assignee or pcOrder for paying rent or other charges due under this
        Sublease, or for performing any other term or covenant of this Sublease.

19)  Default

     a)  Trilogy may terminate this Sublease upon the happening of any one, or
        more, of the following events:

         i)   pcOrder's making a general assignment for the benefit of its
              creditors;

         ii)  The levying on or against pcOrder's property of a writ of
              execution or attachment that is not released or discharged within
              sixty (60) days;

         iii) The institution in a court of competent jurisdiction of
              proceedings for the reorganization, liquidation, or involuntary
              dissolution of pcOrder, or for its adjudication as a bankrupt or
              insolvent, or for the appointment of a receiver of pcOrder's
              property, if the proceedings are not dismissed, and any receiver,
              trustee, or liquidator appointed therein is not discharged within
              sixty (60) days after the proceedings are instituted;

         iv)  pcOrder's doing or permitting to be done any act that creates a
              mechanics' lien or claim against the land or Office Complex of
              which the Subleased Premises are a part that is not released or
              otherwise provided for by indemnification satisfactory to Trilogy
              within sixty (60) days after discovery of the existence of such
              lien by pcOrder; and

         v)   pcOrder's failing to pay any rental installment, or other charge
              or money

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             obligation required by this Sublease, within ten (10) days
             after the date on which such payment is due, or to perform any
             other covenant under this Sublease within thirty (60) days after
             receipt of written notice of such failure from Trilogy.

     b)   Upon any termination of the estate, Trilogy may reenter the Subleased
        Premises, with or without process of law, using such force as necessary,
        and remove all persons and chattels. Trilogy will not be liable for
        damages or otherwise by reason of reentry or termination of the terms of
        this Sublease. Notwithstanding any termination by Trilogy, pcOrder's
        liability for the rents and charges under this Sublease will not be
        relinquished, diminished, or extinguished for the balance of the
        Sublease Term. pcOrder will pay, in addition to the rent and other sums
        agreed to be paid under this lease, any additional sums as the court may
        adjudge reasonable as attorney's fees in any suit or action instituted
        by Trilogy to enforce this Sublease, or the collection of the rent due
        Trilogy if Trilogy prevails in the suit or action. Any property
        belonging to pcOrder or any persons holding by, through, or under
        pcOrder, or otherwise found upon the Subleased Premises, may be removed
        and stored in any public warehouse at the cost of and for the account of
        pcOrder. Should pcOrder abandon, vacate, or surrender the Subleased
        Premises or be dispossessed by process of law, any personal property
        left the Subleased Premises may be deemed abandoned, at Trilogy's
        option.

     c)   If pcOrder breaches this Sublease after expiration of any applicable
        notice and cure period, Trilogy may immediately or at any time
        thereafter, without notice, cure the breach for the account and at the
        expense of pcOrder. If Trilogy at any time, by reason of the breach,
        must pay, or elects to pay, any sum of money or do any act that will
        require paying any sum of money, or must incur any expense, including
        reasonable attorney's fees, in instituting or prosecuting any action or
        proceeding to enforce Trilogy's rights under this Sublease, the sums
        paid by Trilogy, with interest at the rate of twelve percent (12%)
        annually from the date of payment, will be considered additional rent
        and will be due from pcOrder to Trilogy on the first day of the month
        following pcOrder's receipt of a statement from Trilogy of payment of
        the respective sums or expense.

     d)   All Trilogy's rights and remedies enumerated in this Sublease are
        cumulative and will not exclude any other right or remedy allowed by
        law. These rights and remedies may be exercised and enforced
        concurrently, whenever necessary. If Trilogy is in default under this
        Sublease, Trilogy will have sixty (60) days to cure the default after
        written notice to Trilogy by pcOrder specifying such default.

20)  Eminent Domain

If any public authority takes the whole or any part of the Subleased Premises
under the power of eminent domain, then the Sublease Term will cease with
respect to that part from the date that its possession is required for any
public purpose, and the rent will be up to that day. If a portion of the
Subleased Premises is taken so that the remaining portion will not be reasonably
adequate for

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operating pcOrder's business after Trilogy completes such repairs or alterations
as Trilogy is obligated to make, pcOrder may elect either to terminate this
lease or to remain in possession of the remainder of the Subleased Premises. In
the latter event, the rent will be equitably adjusted to account for that
portion of the Subleased Premises so taken. If pcOrder elects to remain in
possession, all the terms of this Sublease will continue in effect except for
rent, and Trilogy will at its own cost and expense make all necessary repairs or
alterations to the Office Complex.

21)  Miscellaneous Provisions

     a)  Corporate Authority

     Trilogy and pcOrder each warrant and represent to the other that this
     Sublease, the transactions contemplated by this Sublease, and the execution
     and delivery of this Sublease, have been duly authorized by all necessary
     corporate proceedings and actions, including without limitation, action on
     the part of the party's board of directors. Certified copies of such
     corporate or other resolutions authorizing this transaction shall be
     delivered by each party to the other.

     b)  Parties Bound

     This Sublease will bind and inure to the benefit of the parties and their
     respective legal representatives, successors, and assigns except as this
     Sublease otherwise specifies.

     c)  Legal Construction

     If any one or more of the provisions of this Sublease is for any reason
     held invalid, illegal, or unenforceable in any respect, that invalidity,
     illegality, or unenforceability will not affect any other provision of this
     Sublease, which will be construed as if it had never included the invalid,
     illegal, or unenforceable provision.

     d)  Prior Agreements Superseded

     This Sublease constitutes the sole agreement of the parties and supersedes
     any prior understandings or written or oral agreements between the parties
     respecting the subject matter.  Notwithstanding the foregoing, Exhibit A to
     this sublease specifies additional lease terms that are in effect through
     12/31/99.

     e)  Attorney's Fees

     If any action at law or in equity, including an action for declaratory
     relief, is brought to enforce or interpret this Sublease, the prevailing
     party is entitled to recover reasonable attorney's fees from the other. The
     fees may be set by the court in the trial of the action or may be enforced
     in a separate action for that purpose, and the fees will be in addition to
     any other relief that may be awarded.

     f)  Specific Performance

     The parties declare that it is impossible to measure in money the damages
     that will accrue to either party, their heirs, executors, administrators,
     legal representatives, successors, or assigns by reason of a failure to
     perform any of the obligations under this Sublease. Therefore, if a party,
     its heirs, executors, administrators, legal representatives, successors,

                                    PAGE 9
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     or assigns institute any action or proceeding to enforce this Sublease, any
     person against whom the action or proceedings are brought agrees that
     specific performance may be sought and obtained for any breach of this
     Sublease.

     g)  Counterparts, One Agreement

     This Sublease and all other copies of it, insofar as they relate to the
     rights, duties, and remedies of the parties, will be considered one
     agreement. This Sublease may be executed concurrently in one or more
     counterparts, each of which will be considered an original, but all of
     which together will constitute one instrument.

     h)  Notice

     Unless this Sublease provides otherwise, any notice, tender, or delivery to
     be given by either party to the other may be effected by personal delivery
     in writing or by registered or certified mail, postage prepaid, return
     receipt requested, and will be considered received as of actual receipt.

     i)  Time of Essence

     Time is of the essence in this Sublease.

     j)  Paragraph Headings

     The paragraph headings used in this Sublease are descriptive only and shall
     have no legal force or effect whatever.

     k)  Texas law

     This Sublease shall be subject to and governed by the laws of the State of
     Texas. Any and all obligations or payments are due and payable in Austin,
     Travis County, Texas.

     l)  Severability

     If any provision of this Sublease shall, for any reason, be held to violate
     of any applicable law, and so much of said agreement is held to be
     unenforceable, the invalidity of such a specific provision shall not
     invalidate any other provisions of this Sublease, which other provisions
     shall remain in full force and effect, unless removal of the invalid
     provisions destroy the legitimate purposes of this Sublease, in which event
     this Sublease shall be cancelled.

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     m)  Relationship Between the Parties

     The relationship between the parties as to this Sublease and the
     transactions described herein is only that of independent contractors, i.e.
     sub-landlord and subtenant. No partnership, joint venture, or relationship
     of principal and agent is intended. pcOrder shall not pledge the credit of
     Trilogy or bind Trilogy to any obligation with respect hereto.

Executed to be effective as of the date first written above.

                              Trilogy Software, Inc., a Delaware corporation


                              By: /s/ PAT KELLY
                                 -----------------------------------
                              Printed Name: Pat Kelly
                                           -------------------------
                              Title: VP - CFO
                                    --------------------------------

                              pcOrder.com, Inc., a Delaware corporation


                              By: /s/ JIM  LUTTENBACHER
                                 -----------------------------------
                              Printed Name: Jim Luttenbacher
                                           -------------------------
                              Title: VP - CFO
                                    --------------------------------

                                    PAGE 11
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Exhibit A


Trilogy and pcOrder.com agree to the following terms:

1.  pcOrder will continue making rent payments to Plaza I (IXC) in accordance
    with their current lease obligation.

2.  Trilogy will reimburse pcOrder for 1/2 floor of rent payments at Plaza II
    (includes base rent and operating expenses) through 12/31/99 (expiration of
    most of Plaza I lease); subject to pcOrder staying current on its lease
    obligations at Plaza I.

3.  Trilogy will work to sublease space at Plaza I; any sublease payments
    received by pcOrder will be passed through to Trilogy. This is in exchange
    for Trilogy paying rent on 1/2 floor at Plaza II.

4.  pcOrder will honor and pay for any buyout agreement that Trilogy negotiates
    related to Plaza I. Trilogy will reimburse pcOrder for any buyout payment
    made by pcOrder.

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