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                                                                    EXHIBIT 10.1
                              EMPLOYMENT AGREEMENT

         THIS EMPLOYMENT AGREEMENT (this "Agreement"), dated as of October 25,
2001, is made and entered into by and between The Advisory Board Company (the
"Company") and Frank Williams (the "Executive").

         1.       EMPLOYMENT. The Company agrees to employ the Executive on the
terms and conditions stated herein to perform and discharge such services and
duties as are reasonably required of the Chief Executive Officer and such other
services and duties as he may be assigned from time to time by the Company's
Board of Directors (the "Board") and such other persons as the Board may
designate. The Executive agrees to accept such employment with the Company and
to devote his full and best efforts, energies and abilities to the Company on a
full-time basis, provided, however, the Executive may serve as a director of any
company that is not, in the sole discretion of the Board, directly or indirectly
in competition with the Company, as long as such service does not interfere with
his duties and obligations to the Company.

         2.       TERM. The term of this Agreement (the "Term") shall commence
upon the initial public offering of the Company's Common Stock (the "Effective
Date") and shall continue until this Agreement is terminated pursuant to Section
7 below.

         3.       COMPENSATION. During the Term, the Company shall pay the
Executive a base salary of Five Hundred Thousand Dollars ($500,000.00) per
annum, payable in installments in accordance with the Company's policy governing
salary payments to executive employees generally. The Board will review the
Executive's salary periodically and may, in its sole discretion, grant increases
to the Executive's salary or pay discretionary bonuses. For the fiscal year
ending March 31, 2002 the Company agrees to pay the Executive a discretionary
bonus of up to One Hundred Thousand Dollars ($100,000.00), with a target amount
of Fifty Thousand Dollars ($50,000.00). The Company shall provide the Executive
with the standard benefits it provides to other senior executive employees, as
such benefits may be modified from time to time.

         4.       EXPENSES. The Company shall reimburse the Executive for all
reasonable and necessary business expenses incurred by him in the performance of
his duties hereunder, in accordance with its policies, and provided they are
vouchered in a form satisfactory to the Internal Revenue Service and consistent
with the Company's policy for the deduction of such expenses.

         5.       COMPLIANCE WITH OTHER AGREEMENTS. The Executive represents and
warrants that (A) his performance hereunder shall not conflict with any
agreement to which he is a party; (B) he will not use in his performance
hereunder any information, material or document of a former employer which is a
trade secret or otherwise confidential or proprietary to such employer, without
first obtaining written authorization for such use from such employer. The
Executive agrees not to enter into any agreement which may conflict with this
Agreement, and authorizes the Company to disclose the terms of this Agreement to
any person or entity.

         6.       NON-COMPETITION AGREEMENT AND INDEMNITY AGREEMENT. On the date
hereof, the Executive and the Company shall execute the Non-Competition
Agreement in the form attached hereto as Exhibit A (the "Non-Competition
Agreement"), and the Indemnity Agreement in the form attached hereto as Exhibit
B (the "Indemnity Agreement"), which are incorporated herein in their entirety
by this reference.

         7.       TERMINATION. If the Executive's employment by the Company is
terminated, the Executive immediately shall resign his position as a director of
the Company. The termination of the Executive's employment by the Company shall
be governed by the following:

         (a)      Termination by the Company for Cause. The Company may
terminate the employment of the Executive for Cause at any time upon three
months' notice. For the purposes of this Agreement the term "Cause" for
termination shall mean the commission of an act of fraud, or theft against the
Company; conviction for any felony; conviction for any misdemeanor involving
moral turpitude which might, in the Company's reasonable opinion, cause
embarrassment to the Company; willful misconduct; or, after receipt of written
notice, willful or repeated (A) violation of Company policy, or (B)
non-performance or substandard performance of duties. In the event of


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termination pursuant to this Section 7(a), the Company may relieve the
Executive's of his duties under this Agreement at any time during the notice
period, provided, that, the Company shall continue to pay the Executive's salary
and benefits during such period. At the end of the notice period, the Executive
shall not be entitled to any further compensation or benefits from the Company
except compensation or benefits earned prior to such date pursuant to the
express terms of this Agreement, or provided for under the Company's Stock-Based
Incentive Compensation Plans between the Company and the Executive (the "Stock
Option Agreements") or the Non-Compete Agreement.

         (b)      Termination by the Company Without Cause or by the Executive
for Good Reason. The Company may terminate the employment of the Executive at
any time without Cause and the Executive may terminate his employment with the
Company for Good Reason at any time upon three months' written notice to the
Company. In the event of termination pursuant to this Section 7(b): (A) the
Company shall continue to pay the Executive's base salary for a period of one
year after termination; (B) all of the stock options granted to the Executive
pursuant to the Stock Option Plans shall vest and immediately become exercisable
and expire one year thereafter; (C) the Executive shall serve as a consultant to
the Company, working a minimum of four days each month at no additional charge
to the Company, for a period of one year. Upon termination pursuant to this
Section 7(b), other than the foregoing, the Executive shall not be entitled to
any further compensation or benefits from the Company except compensation or
benefits earned prior to the date of termination pursuant to the express terms
of this Agreement, or provided for under the Stock Option Agreements or the
Non-Competition Agreement. For the purposes of this Agreement the term "Good
Reason" means, (i) a diminution in the Executive's base salary or title, or (ii)
a material diminution in the Chief Executive Officer's authority, duties, or
responsibilities when compared to the Chief Executive Officer's authority,
duties, or responsibilities at the signing of this agreement.

         (c)      Termination by Death, Disability. The Executive's employment
shall terminate immediately upon his death or disability. For the purposes of
this Agreement, the term "disability" means a serious and permanent medical
incapacity or disability that precludes the Executive from performing his duties
under this Agreement for a continuous period of 180 days. The Company, at its
expense, may retain a physician reasonably acceptable to the Executive to
confirm the existence of such incapacity or disability. In the event of
termination under this Section 7(c), all of the stock options granted to the
Executive pursuant to the Stock Option Plans shall vest and immediately become
exercisable and expire one year thereafter. Other than the foregoing, neither
the Executive nor his estate shall be entitled to any further compensation or
benefits from the Company except compensation or benefits earned prior to the
date of termination pursuant to the express terms of this Agreement, or provided
for under the Stock Option Agreements or the Non-Competition Agreement.

         (d)      Termination by the Executive without Good Reason. The
Executive may terminate his employment without Good Reason at any time upon
three months' written notice to the Company. In the event of termination
pursuant to this Section 7(d), the Company may relieve the Executive's of his
duties under this Agreement at any time during the notice period, provided,
that, the Company shall continue to pay the Executive's salary and benefits
during such period. In the event of termination pursuant to this Section 7(d),
the Executive shall not be entitled to any further compensation or benefits from
the Company except for compensation or benefits earned prior to the date of
termination pursuant to the express terms of this Agreement, or provided for
under the Stock Option Agreements or the Non-Competition Agreement.

         (e)      Change of Control. Upon a Change of Control (A) 50% of all
stock options granted to the Executive under the Stock Option Plans shall vest
and immediately become exercisable on the date of the Change of Control, and (B)
the remaining 50% of all stock options granted to the shall vest and immediately
become exercisable on the second anniversary of the Change of Control. For the
purposes of this Agreement, a "Change of Control" shall have occurred if, as a
result of one or more related transactions after the initial public offering of
the Company's Common Stock, the majority of the capital stock of the Company or
substantially all of its assets are purchased by, or the Company is merged with,
another company. However, a "Change of Control" shall not include a purchase by
or merger with another company if Employee is appointed the CEO of the successor
or combined entity.

         8.       ARBITRATION. The parties shall endeavor to settle all disputes
by amicable negotiations. Any claim, dispute, disagreement or controversy that
arises among the parties relating to this Agreement that is not amicably settled
shall be resolved by arbitration in, as follows:



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         (a)      Any such arbitration shall be heard in the District of
Columbia, before a panel consisting of one arbitrator, who shall be impartial.
Except as the parties may otherwise agree, the arbitrator shall be appointed in
the first instance by the appropriate official in the District of Columbia
office of the American Arbitration Association or, in the event of his or her
unavailability by reason of disqualification or otherwise, by the appropriate
official in the New York City office of the American Arbitration Association. In
determining the number and appropriate background of the arbitrator, the
appointing authority shall give due consideration to the issues to be resolved,
but his or her decision as to the identity of the arbitrator shall be final.
Except as otherwise provided in this Section 9, all of the arbitration
proceedings shall be conducted in accordance with the rules of the arbitrator.

         (b)      An arbitration may be commenced by any party to this Agreement
by the service of a written request for arbitration upon the other affected
parties. Such request for arbitration shall summarize the controversy or claim
to be arbitrated, and shall be referred by the complaining party to the
appointing authority for appointment of arbitrator ten days following such
service or thereafter. If the arbitrator is not appointed by the appointing
authority within thirty days following such reference, any party may apply to
any court within the District of Columbia for an order appointing an arbitrator
qualified as set forth below.

         (c)      The prevailing party in any arbitration under this Section 8
shall be entitled to reimbursement from the losing party of all reasonable
attorneys' fees and costs in connection with such arbitration. The parties
hereby expressly waive punitive damages, and under no circumstances shall an
award contain any amount that in any way reflects punitive damages.

         (d)      Judgment on the award rendered by the arbitrator may be
entered in any court having jurisdiction thereof.

         (e)      It is intended that controversies or claims submitted to
arbitration under this Section 9 shall remain confidential, and to that end it
is agreed by the parties that neither the facts disclosed in the arbitration,
the issues arbitrated, nor the views or opinions of any persons concerning them,
shall be disclosed to third persons at any time, except to the extent necessary
to enforce an award or judgment or as required by law or in response to legal
process or in connection with such arbitration.

         9.       GOVERNING LAW. This Agreement shall be interpreted, construed
and governed according to the laws of the District of Columbia, without regard
to the of conflicts of laws rules thereof.

         10.      HEADINGS AND CAPTIONS. The paragraph headings and captions
contained in this Agreement are for convenience only and shall not be construed
to define, limit or affect the scope or meaning of the provisions hereof.

         11.      SURVIVAL. The provisions of the Non-Competition Agreement, the
Indemnity Agreement and the Stock Option Agreements (and any agreements
incorporated therein by reference) shall survive the termination and/or
expiration of this Agreement.

         12.      ENTIRE AGREEMENT. This Agreement, the Stock Option Agreements,
the Non-Competition Agreement attached hereto as Exhibit A and the Indemnity
Agreement attached hereto as Exhibit B, contain and represent the entire
agreement of the parties and supersede all prior agreements, representations or
understandings, oral or written, express or implied with respect to the subject
matter hereof. To the extent that this Agreement and the Non-Competition
Agreement conflict with any of the Stock Option Agreements or any other
agreement to which the Executive and the Company are parties, the provisions of
this agreement shall govern as between the Executive and the Company.

         13.      SEVERABILITY. If any such provision of this Agreement is held
invalid or unenforceable by a court of competent jurisdiction or any arbitrator,
such provision shall be deleted from this Agreement and this Agreement shall be
construed to give full effect to the remaining provisions hereof.

         14.      WAIVER; AMENDMENT. This Agreement may not be modified or
amended in any way unless in a writing signed by both the Executive and the
Company. It is understood and agreed that one party's failure at any


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time to require the performance by the other party of any of the terms,
provisions, covenants or conditions hereof shall in no way affect the first
party's right thereafter to enforce the same, nor shall the waiver by either
party of the breach of any term, provision, covenant or condition hereof be
taken or held to be a waiver of any succeeding breach.

         15.      ASSIGNMENT. Neither this Agreement nor any rights or
obligations hereunder may be assigned by either party without the prior written
consent of the other. Subject to the foregoing, this Agreement shall be binding
upon and inure to the benefit of the parties hereto, their heirs, successors and
assigns.

         16.      NOTICES. All notices required or permitted hereunder shall be
in writing and shall be deemed properly given if delivered personally or sent by
certified or registered mail, postage prepaid, return receipt requested, or sent
by telegram, telex, telecopy or similar form of telecommunication, and shall be
deemed to have been given when received. Any such notice or communication shall
be addressed: (A) if to the Company, to Chairman of the Board, The Advisory
Board Company, The Watergate, 600 New Hampshire Avenue, N.W., Washington, D.C.
20037; or (B) if to the Executive, to his last known home address on file with
the Company; or to such other address as the parties shall have furnished to one
another in writing.

         17.      COUNTERPARTS. This Agreement may be executed in two or more
counterparts all of which shall have the same force and effect as if all parties
hereto had executed a single copy of this Agreement.

                          [The signature page follows.]




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         IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement, to be effective as of the Effective Date.


                                           THE ADVISORY BOARD COMPANY


/s/ FRANK WILLIAMS                         By: /s/ JEFFREY D. ZIENTS
-------------------------------            ----------------------------------
Frank Williams                      Name:  Jeffrey D. Zients
                                           Title:  Chairman of the Board




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