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                                                                       EX. 10.26


                           VENDOR CONTRACTS AGREEMENT

        THIS VENDOR CONTRACTS AGREEMENT, dated as of July 21, 1998, (this
"Agreement"), is made by and between THE ADVISORY BOARD COMPANY, a Maryland
corporation ("ABC") and THE CORPORATE EXECUTIVE BOARD COMPANY (formerly known as
the Corporate Advisory Board Company), a Delaware corporation ("CEB").

        WHEREAS, ABC and CEB are parties to a Vendor Contracts Agreement, dated
October 31, 1997 (the "Original Agreement");

        WHEREAS, ABC and CEB desire to amend and restate the Original Agreement,
among other things, to extend the term of the Original Agreement through October
31, 1998;

        WHEREAS, the parties hereto desire to amend, modify and restate the
Original Agreement in accordance with the foregoing; and

        WHEREAS, the parties hereto amend and restate the following recitals:

                                    RECITALS

        A.      ABC and CEB have entered into a Distribution Agreement dated as
of October 31, 1997 (the "Distribution Agreement"), providing for the
contribution by ABC of the Transferred Business to CEB.

        B.      Following the Contribution, subject to the conditions set forth
in the Distribution Agreement, all issued and outstanding shares of capital
stock of CEB were distributed to the Sole Stockholder.

        C.      In the interest of an orderly transition with respect to the
transfer of the Transferred Business to CEB and certain third-party vendor
contracts relating thereto (the "Vendor Contracts"), the parties desire to
provide for (i) the provision during the Transition Period of services pursuant
to the Vendor Contracts (the "Vendor Services") to CEB or ABC as appropriate and
(ii) the appropriate allocation of related costs and expenses relating to such
Vendor Services.

        The parties agree as follows:

        1.      Definitions. Unless the context otherwise requires, capitalized
terms not otherwise defined herein shall have the respective meanings given to
them in the Distribution Agreement.

        2.      Vendor Services.

        (a)     The Vendor Contracts are set forth in Attachment 1 hereto.
Subject to the terms of this Agreement, upon the written request setting forth
additional or amended Vendor Services to be provided to CEB made by an Executive
Vice President of CEB or a person designated to act on his behalf in an
instrument executed by such CEB Executive Vice President and



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delivered to ABC, ABC shall provide, or cause provision, to CEB of each of the
Vendor Services with respect to the Transferred Business in the manner and to
the same general extent as such Vendor Services have been provided to ABC in
connection with the Transferred Business before the Contribution.

        (b)     Costs and expenses relating to Vendor Contracts shall be
allocated as shall be determined by the parties as follows or as otherwise shall
be mutually agreed in writing by the parties:

                (i)     Segregate Vendor Contract Invoices: If invoices relating
                to Vendor Services can be divided to reflect properly the Vendor
                Services provided to ABC and CEB, respectively, such invoices
                shall be segregated and paid directly by the appropriate party
                to whom the related Vendor Services were provided.

                (ii)    Reimburse ABC: In the event that invoices relating to
                Vendor Services cannot be segregated and paid as described in
                subparagraph (i) above, CEB shall pay its allocated share
                directly or reimburse ABC for Vendor Services provided to CEB
                pursuant to this Agreement as set forth in Attachment 1.

        3.      Term. Except with respect to Section 6, the term of this
Agreement shall be two (2) years commencing on October 31, 1997 (the "Term").
CEB shall have the right to terminate a Vendor Service or Vendor Services upon
sixty (60) days prior written notice to ABC. Termination of one or more Vendor
Services by CEB shall not affect the obligation of ABC to furnish all other
Services for the remainder of the Term.

        4.      Nondisclosure. In the event that, during the Term and in
connection with a party's performance of its obligations hereunder, either party
shall receive information concerning the other party hereto which the receiving
party knows, or has reason to believe, is confidential or proprietary to the
party to whom such information relates, the party receiving such information
shall take all reasonable steps to (a) protect and hold such information in
confidence and prevent its disclosure to third parties unless such third parties
are under a duty of confidentiality to the party to which such information
relates; and (b) restrict its use to those purposes consented to in writing by
the party to whom such information relates; provided, however, that the party
receiving such information shall not be required to protect or hold in
confidence any information or data which (i) is or becomes available to the
public without the fault of the receiving party, (ii) is independently developed
by the receiving party, (iii) is disclosed to the receiving party by a third
party known to the receiving party not to be under any duty of confidentiality
to the party to whom such information relates with respect to such information
or (iv) except as may otherwise be required by law. This Section 4 shall not
limit the obligation of the parties under the Distribution Agreement to provide
access to records after the date hereof.

        5.      Limitation on Liability. ABC's liability to CEB in connection
with this Agreement and the Vendor Services to be provided by ABC shall be
limited to actual damages arising from ABC's gross negligence or willful
misconduct in the performance of its duties and responsibilities hereunder;
provided, however, that, in no event shall ABC be liable for any incidental or
consequential damages.



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        6.      Indemnity.

        (a)     ABC agrees to defend, indemnify and hold CEB and its officers,
directors, employees and agents harmless from and against all liabilities,
losses, claims, damages and expenses of any nature, including reasonable
attorneys' fees, that are reasonably incurred by CEB arising out of the
performance of the Services hereunder, except where such liability, loss, claim,
damage or expense shall have been caused by CEB's gross negligence or willful
misconduct in the performance of its duties and responsibilities hereunder.

        (b)     CEB agrees to defend, indemnify and hold ABC and its officers,
directors, employees and agents harmless from and against all liabilities,
losses, claims, damages and expenses of any nature, including reasonable
attorneys' fees, that are reasonably incurred by ABC arising out of the
performance of the Services hereunder, except where such liability, loss, claim,
damage or expense shall have been caused by ABC's gross negligence or willful
misconduct in the performance of its duties and responsibilities hereunder.

        7.      Mutual Cooperation. ABC and CEB will provide each other with
information and assistance reasonably necessary to investigate, defend or
prosecute any claims, suits, charges, including but not limited to equal
employment opportunity, workers compensation, insurance and similar claims
brought by or against ABC or CEB relating to either of their businesses. This
provision shall survive termination of this Agreement.

        8.      Third Party Rights. Nothing in this Agreement, express or
implied, is intended to confer upon any person (including, without limitation,
employees), other than the parties hereto and their respective successors and
assigns, any rights or remedies of any nature whatsoever under or by reason of
this Agreement.

        9.      Relationship of Parties. Nothing in this Agreement shall be
deemed or construed by the parties or any third party as creating the
relationship of principal and agent, partnership or joint venture between the
parties, it being understood and agreed that no provision contained herein, and
no act of the parties, shall be deemed to create any relationship between the
parties other than the relationship of independent contractor nor be deemed to
vest any rights, interest or claims in any third parties.

        10.     Successor and Assigns. This Agreement shall inure to the benefit
of and be binding upon the respective successors and assigns of the parties
hereto, provided that this Agreement may not be assigned by either of the
parties hereto without the prior written consent of the other.

        11.     Notices. All notices and other communications required or
permitted to be given under this Agreement shall be in writing and shall be
deemed to have been duly given if delivered by hand or mailed, postage prepaid
or by certified or registered mail, and addressed to the applicable party at the
respective addresses set forth in the Distribution Agreement (or at such other
address for a party as shall be specified by a like notice).

        12.     Governing Law. The validity, enforceability and performance of
this Agreement shall be governed by and construed in accordance with the laws of
the State of Maryland (excluding its choice of law rules).



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        13.     Entire Agreement. The parties intend that the terms of this
Agreement, including the attached schedules, shall be the final expression of
their agreement with respect to the subject matter hereof and may not be
contradicted by evidence of any prior or contemporaneous agreement. The parties
further intend that this Agreement shall constitute the complete and exclusive
statement of its terms and that no extrinsic evidence whatsoever may be
introduced in any judicial, administrative or other legal proceedings involving
this Agreement.

        14.     Counterparts. This Agreement may be executed in counterparts,
each of which shall be deemed an original, but all of which taken together shall
constitute one and the same instrument.

        15.     Headings. The headings used in this Agreement are inserted for
convenience of reference only and shall not affect the meaning or interpretation
of any provision of this Agreement.

        16.     Amendments and Waivers. This Agreement may not be amended except
upon the written consent of all of the parties. By an instrument in writing, any
party may waive compliance by any other party with any term or provision of this
Agreement that such other party was or is obligated to comply with or perform,
provided, however, that such waiver shall not operate as a waiver of, or
estoppel with respect to, any other or subsequent failure. No failure to
exercise and no delay in exercising any right, remedy, or power hereunder shall
operate as a waiver thereof, nor shall any single or partial exercise of any
right, remedy, or power hereunder preclude any other or further exercise thereof
or the exercise of any other right remedy, or power provided herein or by law or
in equity. The waiver by any party of the time for performance of any act or
condition hereunder does not constitute a waiver of the act or condition itself.

        17.     Expenses. Whether or not the transactions contemplated in this
Agreement are consummated, unless specifically provided otherwise in this
Agreement (including all Schedules hereto), each party shall bear and pay all
expenses incurred by it or on its behalf in connection with the preparation of
this Agreement and consummation of the transactions described herein.

        18.     Severability. If any provision of this Agreement, or the
application thereof to any person, place or circumstance, shall be held by a
court of competent jurisdiction to be void, invalid or unenforceable, the
remainder of this Agreement and such provisions as applied to other persons,
places or circumstances shall remain in full force and effect.




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        IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their duly authorized officers as of the date first above written.


                                            THE ADVISORY BOARD COMPANY,
                                            a Maryland corporation



                                            By:
                                               ---------------------------------


                                            Its:
                                                --------------------------------

                                            THE CORPORATE EXECUTIVE BOARD
                                            COMPANY, a Delaware corporation


                                            By:
                                               ---------------------------------


                                            Its:
                                                --------------------------------






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