Document:

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                                                                   EXHIBIT 10.24

                                 PROMISSORY NOTE

$220,000.00                                                       March 31, 2001

FOR VALUE RECEIVED, the undersigned, Scott A. Schirmeier ("Borrower"), an
employee of the Advisory Board Company with his principal residence at 2418 19th
Street, N.W. # 29, Washington, D.C., promises to pay to order of the Advisory
Board Company, a Maryland corporation with its place of business at 600 New
Hampshire Avenue, N.W., Washington, D.C., the principal sum of $220,000.00 with
interest at the rate of seven percent (7%) per annum, subject to the terms and
conditions herein contained.

        1.      The principal sum shall be due and payable on the earlier of (i)
the date the Borrower sells Advisory Board Company stock pursuant to an exercise
of Advisory Board Company options, (ii) the date the Borrower has Advisory Board
Company options repurchased by the Company, (iii) thirty days prior to the
expiration of any of the Borrower's Advisory Board Company options, or (iv) the
date the Borrower leaves the employ of the Advisory Board Company for any
reason.

        2.      Interest on the outstanding balance of the principal sum shall
accrue at the rate of seven percent (7%) per annum from March 31, 2001 until
this Note is paid in full.

        3.      This Note may be prepaid in whole or in part at any time without
penalty.

        4.      This note is secured by all real and personal property of the
Borrower.

        5.      Upon the occurrence of an Event of Default, as that term is
defined below, and the continuation of any such Event of Default for a period of
thirty days after the delivery of written notice to the undersigned setting,
forth such Event of Default, the unpaid balance of the. principal and any
interest accrued thereon shall, at the option of the holder hereof, at once
become due and payable. The notice of default shall be deemed to be delivered if
sent by United States or registered mail to the undersigned at the address set
forth above.

An Event of Default will be deemed to have occurred if:

                (a)     Debtor fails to pay the principal payments and accrued
        interest when due in accordance with the Note.

                (b)     Debtor files a voluntary proceeding under the Bankruptcy
        Code, or any involuntary petitions under the Bankruptcy Code are filed
        against the Debtor.

        6.      Any payment by the undersigned on this Note shall be credited
first to any interest then due, and the remainder on the principal sum, and
interest shall thereupon cease to accrue upon the amount so credited on the said
principal sum.

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IN WITNESS WHEREOF, the undersigned has set its hand and seal as of the day,
month and year first hereinabove written.

Creditor:                                                Debtor:

The Advisory Board Company, Inc.                         Scott A. Schirmeier

/s/Michael D'Amato                                       /s/ SCOTT A. SCHIRMEIER
-----------------------------------                      -----------------------
Michael D'Amato
Executive Vice President

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                                                                       EX. 10.25

                        ADMINISTRATIVE SERVICES AGREEMENT

        THIS ADMINISTRATIVE SERVICES 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 Management Services 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.      During the Transition Period, ABC desires to provide, and CEB
desires to receive, certain administrative and other corporate services from
ABC, as hereinafter specifically provided (collectively, the "Administrative
Services" and, individually, a "Administrative Service"), and the parties desire
to set forth herein the basis on which the Administrative Services shall be
provided to CEB.

        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.      Administrative Services. The specific Administrative Services to
be provided by ABC to CEB are comprised of the services more particularly set
forth in Attachment 1 hereto. Subject to the terms of this Agreement, upon the
written request setting forth additional or amended Administrative 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 delivered to ABC, ABC shall provide each of such additional
or amended Administrative Services with respect to the Transferred Business in
the manner and to

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the same general extent as such Administrative Services have been provided by
ABC in connection with the Transferred Business before the Contribution.

        3.      Term. Except with respect to Section 12, the term of this
Agreement shall be two (2) years commencing on October 31, 1997 (the "Term").
Services shall be provided only as specified in Attachment 1 hereto, unless
otherwise agreed to by the parties. In addition, CEB shall have the right to
terminate an Administrative Service or the Administrative Services upon sixty
(60) days prior written notice to ABC. Termination of one or more Administrative
Services by CEB shall not affect the obligation of ABC to furnish all other
Administrative Services for the remainder of the Term.

        4.      Cost. Unless otherwise expressly agreed in writing by a duly
authorized officer of ABC and CEB, the Administrative Services shall be provided
to CEB in consideration for payment to ABC of the administrative fees set forth
in Attachment 1.

        5.      Delegation. ABC may retain the services of such third parties,
either by oral or written contract, as ABC may, from time to time, deem
necessary or appropriate to facilitate the expeditious discharge of ABC's
responsibilities hereunder.

        6.      Independence. All employees and representatives of ABC providing
Administrative Services to CEB will be deemed for purposes of all compensation
and employee benefits to be employees or representatives of ABC and not
employees or representatives of CEB. In performing such Administrative Services,
such employees or representatives will be under the direction, control and
supervision of ABC (and not CEB) and ABC will have the sole right to exercise
all authority with respect to the employment (including termination of
employment), assignment and compensation of such employees and representatives.
ABC shall be solely responsible for the payment of all payroll and withholding
taxes relating to its employees for services provided to CEB during the Term.

        7.      Impracticability. ABC shall not be required to provide any
Administrative Service to the extent the performance or the provision of such
Administrative Service becomes impracticable as a result of a cause or causes
outside of the reasonable control of ABC, or to the extent the performance of
such Administrative Service would require ABC to violate applicable laws, rules
or regulations or result in the breach of any license, permit or applicable
contract.

        8.      Additional Resources. In providing the Administrative Services,
ABC shall not be obligated to: (i) hire any additional employees, (ii) maintain
the employment of any specific employee, or (iii) purchase, lease or license any
additional equipment or software.

        9.      Force Majeure. The obligations of ABC under this Agreement are
subject to conditions of force majeure, including an act of God, strike or
walkout or other labor dispute, act of a public enemy, war, revolution, riot,
fire, storm, flood, earthquake, embargo and any other cause which is not
reasonably within the control of the party affected thereby.

        10.     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

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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 10 shall not
limit the obligation of the parties under the Distribution Agreement to provide
access to records after the date hereof.

        11.     Limitation on Liability. ABC's liability to CEB in connection
with this Agreement and the Administrative 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.

        12.     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 Administrative 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 Administrative 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.

        13.     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.

        14.     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.

        15.     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

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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.

        16.     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.

        17.     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).

        18.     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).

        19.     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.

        20.     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.

        21.     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.

        22.     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.

        23.     Expenses. Whether or not the transactions contemplated in this
Agreement are consummated, unless specifically provided otherwise in this
Agreement (including all Schedules

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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.

        24.     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.

        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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