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                                                                    EXHIBIT 10.2



                            NON-COMPETITION AGREEMENT

        This Non-Competition Agreement (this "Agreement") dated as of October
25, 2001, is made and entered into by The Advisory Board Company, including its
affiliates, successors, and assigns (the "Company") and Frank Williams (the
"Executive").

                                 R E C I T A L S

        WHEREAS, the Company has offered employment to the Executive pursuant to
an Employment Agreement dated as of the date hereof; and

        WHEREAS, the Company and the Executive agree that it is reasonable and
necessary to enter into this Agreement to protect the Company's good will, its
base of members and prospective members, its employees, its confidential and
proprietary information, and its work product.

        NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which is acknowledged,
the parties agree as follows:

        1.      CONFIDENTIAL INFORMATION. Except as may be required and
authorized in the course of his employment with the Company, the Executive shall
not at any time during his employment with the Company or after the termination
thereof for any reason disclose or use, directly or indirectly, any confidential
or proprietary information of the Company or its affiliates. For the purposes of
this Agreement, "confidential or proprietary information" shall mean all
information disclosed to the Executive, or known by him as a consequence of or
through his employment with the Company, where such information is not generally
known in the trade or industry or which is considered confidential by the
Company or was the subject of efforts by the Company to maintain its
confidentiality, and where such information refers or relates in any manner
whatsoever to the business activities, processes, services or products of the
Company or its affiliates. Such information includes, but is not limited to,
trade secrets as defined by the District of Columbia Trade Secrets Act, D.C.
Code Section 48-501, et seq., business and development plans (whether
contemplated, initiated or completed), business contacts, methods of operation,
policies, results of analysis, member and prospective member lists, employee
lists, business forecasts, financial data, advertising and marketing methods,
manuals, training materials, management, performance review, project assessment
and all other forms and documents used in management of the Company's employees
and in performing work for the Company, reports, correspondence, data collection
forms and other documents provided to members, syndicated, multi-client studies,
custom research reports, statements, reports, strategic information and other
information distributed to policy or management committee members, information
relating to costs and revenues, and similar information. The restrictions on the
Executive's use and disclosure of confidential or proprietary information of the
Company set forth in this Section 1 shall not apply when and to the extent that
the confidential or proprietary information is or becomes available to the
public or widely known in the applicable industry through no fault of the
Executive (or anyone acting on his behalf), or the Executive is legally
compelled to disclose the confidential or proprietary information of the
Company. In the event that the Executive is legally compelled to make such
disclosure, he shall (i) provide the Company with prompt written notice thereof
prior to the disclosure, (ii) use his best efforts and cooperate with the
Company, to seek, at the Company's expense, a protective order or confidential
treatment for the disclosed information, and (iii) disclose only that portion of
the or proprietary information of the Company that is legally required to be
furnished.

        2.      RETURN OF COMPANY PROPERTY. Upon termination of employment for
any reason, the Executive shall immediately return to the Company all of the
Company's and its affiliates' property and confidential or proprietary
information which is in tangible form (including, but not limited to, all
correspondence, memoranda, files, manuals, books, lists, records, equipment,
computer disks, magnetic tape, and electronic and other media and equipment) and
all copies thereof in the Executive's possession, custody or control.

        3.      BUSINESS OPPORTUNITIES. During the term of his employment, the
Executive shall promptly disclose to the Company each business opportunity of a
type which, based upon its prospects and relationship to the business of the
Company or its affiliates, the Company might reasonably consider pursuing. In
the event that the Executive's employment is terminated for any reason, the
Company or its affiliates shall have the exclusive right to


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participate in or undertake any such opportunity on their own behalf without any
involvement by or compensation to the Executive.

        4.      COVENANT NOT TO COMPETE.

        If the Executive's employment is terminated for any reason, the
Executive shall not, directly or indirectly, either individually or as a five or
more percent stockholder, director, officer, partner, consultant, owner,
employee, agent, or in any other capacity, for a period of two years following
such termination, (i) provide Company Services or work for or provide services
to any person or entity that provides Company Services, within a one hundred
mile radius of any city or location in the United States or in any foreign
country in which the Company or its affiliates has an office, is engaged in
business, or proposes to engage in business as of the date of the Executive's
termination; or (ii) solicit or offer to provide or provide Company Services, or
work for a person or entity that solicits or offers to provide or provides
Company Services, to any person or entity who was a member of the Company or its
affiliates or was directly or indirectly solicited to be a member of the Company
or its affiliates at any time during the two-year period prior to the
termination of the Executive's employment with the Company. For the purposes of
this Agreement, the term "Company Services" shall mean membership based
subscription or implementation services substantially similar to the services
provided by the Company as of the date of the Executive's termination, in which
members receive services incorporating some combination of the following:
multi-client syndicated studies, meetings, short answer custom research, and on
site seminars or implementation support. Notwithstanding the foregoing, the
Executive may upon termination in the situations described above work as a
consultant or for a consulting firm, provided he complies with all of the
provisions of this Section 4. Upon the written approval of its Board of
Directors, the Company may release the Executive from some or all of the
restrictions in this Section 4.

        5.      SOLICITATION OF EMPLOYEES. The Executive agrees that during the
term of his employment, and for a period of two years after termination of such
employment, he shall not, except in the course of his duties for the Company,
directly or indirectly, induce or attempt to induce or otherwise counsel,
advise, ask or encourage any person who at the time is a current employee of the
Company or its affiliates, or who left such employ within the preceding 12
months, to leave the employ of the Company or to accept employment with another
employer besides the Company or as an independent contractor, or offer
employment to or hire such person.

        6.      INVENTIONS IMPROVEMENTS AND COPYRIGHTABLE MATERIALS. The
Executive shall disclose promptly in writing and assign immediately, and hereby
assigns to the Company, all of the Executive's right, title and interest in and
to, any original works of authorship, formulas, processes, programs,
benchmarking or other databases, techniques, know-how, data, developments or
discoveries, whether or not copyrightable (hereinafter referred to collectively
as "Work Product"), which the Executive may make or conceive, or first reduce to
practice or learn either solely or jointly with others, during the employment
period with the Company through the Executive's work with the Company or its
affiliates or with any other person or entity pursuant to an assignment by the
Company or its affiliates. The Executive acknowledges the special interest the
Company holds in its processes, techniques and technologies in producing its
editorial works and agrees that such processes, techniques and technologies
shall not be directly or indirectly used or distributed by the Executive for the
interests of any person or entity besides the Company. All disclosures and
assignments made pursuant to this Agreement are made without royalty or any
additional consideration to the Executive other than the regular compensation
paid to the Executive by the Company or its affiliates.

        7.      COMPLIANCE. Upon the request of the Company, the Executive
agrees to provide the Company with such information as may be reasonably
necessary to demonstrate his compliance with the terms and conditions of this
Agreement.

        8.      SEVERABILITY. The Executive agrees that the restrictions imposed
upon him by the provisions of this Agreement are fair and reasonable considering
the nature of the Company's business, and are reasonably required for the
protection of the Company. To the extent that any of the restrictions this
Agreement are found to exceed maximum enforceable restrictions by a court of
competent jurisdiction, such restrictions shall be modified by such court to
reflect the maximum level of restriction which such court will enforce. If any
provision of this Agreement shall be determined, by a court having jurisdiction,
to be invalid, illegal or unenforceable, the remainder of this Agreement shall
not be affected but shall continue in full force and effect as though such
invalid, illegal or unenforceable provision were not originally a part of this
Agreement.

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        9.      INJUNCTIVE RELIEF AND ATTORNEYS' FEES. The Executive
acknowledges that a breach of any of the provisions of this Agreement may result
in continuing and irreparable damages to the Company or its affiliates for which
there may be no adequate remedy at law and that the Company or its affiliates in
addition to all other relief available to it shall be entitled to the issuance
of a temporary restraining order, preliminary injunction and permanent
injunction restraining the Executive from committing or continuing to commit any
breach of this Agreement both pending further legal proceedings and for
appropriate periods in the future. The prevailing party in any action for breach
of this Agreement, shall be entitled to reimbursement from the losing party for
its reasonable attorneys' fees and costs incurred in such action. The Executive
agrees that any applicable time period limitation on any provision of this
Agreement (such as the two-year limitation period set forth in Section 4) shall
be extended on a day-for-day basis for each day during which the Executive
participates in any activity in violation of any such provision.

        10.     CHOICE OF LAW. This Agreement shall be construed in accordance
with and governed by the laws of the District of Columbia, irrespective of the
conflicts of law rules thereof.

        11.     SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon and
shall inure to the benefit of the parties and their respective successors and
assigns. Notwithstanding the foregoing, the Executive may not assign his
obligations under this Agreement without the express written consent of the
Company and its successors and assigns.

                          [The signature page follows.]


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               IN WITNESS WHEREOF, the parties have executed this Agreement as
of the date first above written.

EMPLOYEE                                      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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