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                                                                    EXHIBIT 10.4


                            NON-COMPETITION AGREEMENT


        This Agreement is entered into effective January 1, 1999, by and among
The Corporate Executive Board Company, a Delaware corporation, including its
subsidiaries, successors and assigns (collectively, "CEB"), The Advisory Board
Company, a Maryland corporation, including its subsidiaries, successors and
assigns (collectively, "ABC") and David G. Bradley, including his successors,
assigns and any entity controlled by him (collectively, "Bradley").

        WHEREAS, CEB, ABC and Bradley desire to enter into an agreement to place
certain limitations on competition between CEB, on the one hand, and, on the
other hand, ABC and Bradley (ABC and Bradley together are referred to herein as
the "Bradley Parties").

        NOW, THEREFORE, in consideration of the premises and covenants contained
herein and intending to be legally bound hereby, CEB, ABC and Bradley agree as
follows:

1.      DEFINITIONS.

        (a)    "Covered Services" shall mean membership based subscription
               services substantially similar to the services provided by ABC
               and CEB as of the date of this agreement, in which members
               receive a bundle of services incorporating a meaningful
               combination of the following: multi-client syndicated studies,
               meetings focused on discussions of syndicated studies, short
               answer custom research, and on site seminars.

        (b)    "Health Care Provider Company" shall mean any company or
               institution, or any division or subsidiary of any company or
               institution, that is principally engaged in the health care
               provider business, which shall include providers of patient care
               (such as hospitals, outpatient facilities, home health agencies
               and relevant government agencies) and providers of medical
               professional services (such as physician and nursing services and
               physician practice management companies).

        (c)    "Other Health Care Company" shall mean any company or
               institution, or any division or subsidiary of any company or
               institution, that is not a Health Care Provider Company and which
               is principally engaged in other types of health care business,
               including: pharmaceuticals companies; medical supply companies;
               medical equipment companies; technology, software,
               communications, financing and services vendors selling
               predominantly to Health Care Provider Companies; companies
               providing health insurance; and managed care companies.

        (d)    "Non-Health Care Company" shall mean any company or institution,
               or any division or subsidiary of any company or institution, that
               is not a Health Care Provider Company or an Other Health Care
               Company.




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2.      NON-COMPETITION.

        (a)    THE BRADLEY PARTIES. The Bradley Parties shall not offer or sell
               Covered Services to any Non-Health Care Companies.
               Notwithstanding the forgoing, the Bradley Parties may:

               (i)    sell products and services to any company or institution,
                      or any division or subsidiary of any company or
                      institution, that is a Health Care Provider Company;

               (ii)   sell products and services to divisions and subsidiaries
                      of companies other than Health Care Provider Companies, if
                      such divisions or subsidiaries themselves are Health Care
                      Provider Companies; and

               (iii)  continue to renew pre-existing subscriptions with respect
                      to those products and services that it has sold as of the
                      closing date of the initial public offering of shares of
                      Common Stock of CEB (the "Offering Date") to any then
                      existing client, if such client was a subscriber to such
                      products or services immediately prior to such
                      subscription renewal and such products and services
                      specifically address health care provider industry issues;
                      and

               (iv)   offer and sell to any entity:

                      (A)    magazines, newspapers and news services;

                      (B)    advertising for its publications, news or
                             on-line services; and

                      (C)    products and services that are specifically
                             addressed to and deal with advertising and
                             promotion activities by companies and institutions
                             and advertising agencies, provided that such
                             products and services are offered only to the
                             offices and divisions of companies, institutions or
                             advertising agencies that are responsible for the
                             placement or designing of advertisements;

                      (D)    products and services that are specifically
                             addressed to and deal with government relations and
                             lobbying activities by companies and institutions,
                             provided that such products and services are
                             offered only to the offices and divisions of
                             companies or institutions that are responsible for
                             government relations and lobbying.

        (b)    CEB. CEB shall not offer or sell Covered Services to Health Care
               Provider Companies. Notwithstanding the forgoing, CEB may:

               (i)    sell its products and services to Non-Health Care
                      Companies;




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               (ii)   sell its products and services to divisions and
                      subsidiaries of companies other than Non-Health Care
                      Companies, if such divisions or subsidiaries are
                      themselves Non-Health Care Companies; and

               (iii)  continue to renew pre-existing subscriptions with respect
                      to those products and services that it has sold as of the
                      Offering Date to any then existing client, if such client
                      was a subscriber to such products or services immediately
                      prior to such subscription renewal and such products and
                      services do not specifically address health care provider
                      industry issues.

        (c)    PROVISION OF SERVICES TO OTHER HEALTH CARE COMPANIES.
               Notwithstanding the forgoing:

               (i)    the Bradley Parties may sell Covered Services to Other
                      Health Care Companies provided that Bradley Parties do not
                      offer programs targeted to the same executives and
                      covering the same subjects as that of CEB's Human
                      Resources, Chief Financial Officer or General Counsel
                      programs; and also provided that all research agendas,
                      brochures and any other sales and marketing materials
                      associated with such services make explicit the health
                      care industry focus of such services.

               (ii)   CEB may sell Covered Services to Other Health Care
                      Companies, only if such services are of a general business
                      nature and are also sold by CEB principally to Non-Health
                      Care Companies.

3.      EMPLOYEES.

        (a)    Except as provided in Section 3(c) of this Agreement, the Bradley
               Parties shall not recruit or employ any person who is at the time
               of such recruitment an employee of CEB, or who was employed by
               CEB at any time during the 24-month period preceding the date of
               such recruitment or employment, unless CEB's chief executive
               officer consents to such recruitment and employment.

        (b)    CEB shall not recruit or employ any person who is at the time of
               such recruitment an employee of ABC or Bradley, or who was
               employed by ABC or Bradley at any time during the 24-month period
               preceding the date of such recruitment or employment, unless
               ABC's chief executive officer or Bradley, as the case may be,
               consents to such recruitment and employment.

        (c)    Bradley or ABC may hire Derek C. van Bever, the Chief Research
               Officer of CEB, at any time after January 1, 2002.

        (d)    Each of CEB and ABC shall incorporate in each of the
               noncompetition agreements that it has entered into, or will
               enter into, with its current or future employees provisions (the
               "Noncompetition Provision") that would prohibit such employee
               from competing with CEB or ABC, as the case may be, to the same
               extent and under the same terms and conditions that similar
               level employees



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               generally are prohibited from competing with the company
               employing such employee, and that would impose similar
               restrictions on the use of confidential information. Neither CEB
               nor ABC shall waive any rights under, or agree to any
               settlements in connection with the enforcement of, the
               Noncompetition Provision contained in any noncompetition
               agreement without the prior written consent of the other
               company, but only to the extent that such waiver or such
               settlement relates to the rights of such other company. Each of
               CEB and ABC shall use its best efforts to enforce the
               Noncompetition Provision promptly upon being notified or
               becoming aware of a breach of such provision by any of its
               current or previous employees who are subject to the
               Noncompetition Provision; provided, however, that the company
               for whose benefit the Noncompetition Provision is being enforced
               shall pay all reasonable costs and expenses incurred in
               connection with such enforcement. In addition, each company may
               assert directly its own rights under the Noncompetition
               Provision with respect to current or previous employees of the
               other company to the maximum extent permitted by law.

4.      NAME LICENSE.

        (a)    ABC continues to own all rights, title, interest and any other
               intellectual property or proprietary right in the name "The
               Advisory Board Company" and all derivations thereof, including
               but not limited to, "The Corporate Advisory Board Company" and
               CEB has no right or interest therein, except for the license
               granted in Section 4(b) below.

        (b)    ABC hereby grants an exclusive, non-transferable, royalty-free,
               paid-up license to CEB to use the derivative name "The Corporate
               Advisory Board Company" for a period of two years from the date
               of this Agreement only for Transitional Purposes, provided that,
               the name "The Corporate Advisory Board Company" may be used for
               recruiting of prospective employees only if CEB receives prior
               written approval from ABC. "Transitional Purposes" shall mean
               for purposes of this Section, use of the name to inform the
               general public that The Corporate Advisory Board Company has
               changed its name to The Corporate Executive Board Company. Upon
               the expiration of the two-year period, all rights, title and
               interest in the name "The Corporate Advisory Board Company" will
               revert back to ABC.

        (c)    ABC shall not use the name "The Corporate Advisory Board Company"
               or any other derivation of its name with the word "Corporate"
               during the term of this agreement.

5.      TERM.

        The term of this Agreement will commence on the date first written in
the preamble above and will end on the date that is five years from such date.



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6.      FURTHER ASSURANCES.

        CEB, ABC and Bradley agree that at any time and from time to time, upon
written request, they will execute and deliver such further documents and do
such further acts and things as may be reasonably requested in order to
effectuate the purposes of this Agreement and the transactions contemplated
hereby.

7.      GOVERNING LAW.

        This Agreement will be governed by and construed in accordance with the
internal laws of the State of Delaware (excluding its choice of law rules).

8.      ARBITRATION.

        The parties shall endeavor to settle all disputes by amicable
negotiations. Any claim, dispute, disagreement or controversy that arises among
the parties ("Disputed Matter") relating to this Agreement that is not amicably
settled shall be referred to and settled by arbitration administered by the
American Arbitration Association in accordance with the Expedited Procedures of
the Commercial Arbitration Rules of the American Arbitration Association (the
"AAA Rules") by a single arbitrator who is mutually agreeable to the parties. If
the parties are unable to agree upon an arbitrator, one arbitrator shall be
selected in accordance with the AAA Rules. All proceedings in any such
arbitration shall be conducted in Washington, D.C. Each party to such
arbitration proceeding shall bear its respective costs, fees and expenses in
connection with such arbitration. Upon a final determination by the arbitrator
with respect to the Disputed Matter, the arbitrator shall notify the parties
(such notice being the "Arbitration Order"). Any judgment on the award rendered
by the arbitrator may be entered in any court having jurisdiction thereof.
Jurisdiction of such arbitrator shall be exclusive as to disputes among the
parties relating to this Agreement and each of the parties agrees that this
Agreement to arbitrate shall be specifically enforceable under the laws of the
respective domiciliary jurisdictions of the parties. None of the parties shall
have the right to appeal the Arbitration Order or otherwise to submit a dispute
relating to this Agreement to a court of law.

9.      COUNTERPARTS.

        This Agreement may be executed in counterparts, each of which will
constitute an original and all of which will be one and the same document.



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


                                  THE CORPORATE EXECUTIVE BOARD COMPANY


                                   /s/ JAMES J. MCGONIGLE
                                  -----------------------------------
                                  By:    James J. McGonigle
                                  Its:   Chief Executive Officer








                                  THE ADVISORY BOARD COMPANY




                                  /s/ JEFFREY D. ZIENTS
                                  -----------------------------------
                                  By:    Jeffrey D. Zients
                                  Its:   Chief Executive Officer


                                        /s/ DAVID G. BRADLEY
                                  ------------------------------------
                                         David G. Bradley

















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