Exhibit 10.21
 THE CORPORATE EXECUTIVE BOARD COMPANY
STANDARD TERMS AND CONDITIONS FOR
RESTRICTED STOCK UNITS
  1.
    
    TERMS OF RESTRICTED STOCK UNITSTHE CORPORATE EXECUTIVE BOARD COMPANY, a Delaware corporation (the Company), has granted to
the Participant named in the Term Sheet provided to said Participant herewith (the Term
Sheet) an award of a number of restricted stock units (the Award) specified in the Term
Sheet. Each restricted stock unit represents the right to receive one share of the Companys
Common Stock, $0.01 par value per share (the Common Stock), upon the terms and subject to
the conditions set forth in the Term Sheet, these Standard Terms and Conditions, and the
Plan, each as amended from time to time. For purposes of these Standard Terms and Conditions
and the Term Sheet, any reference to the Company shall, unless the context requires
otherwise, include a reference to any Subsidiary, as such term is defined in the Plan.2.
    
    VESTING OF RESTRICTED STOCK UNITSThe Award shall not be vested as of the Grant Date set forth in the Term Sheet and shall be
forfeitable unless and until otherwise vested pursuant to the terms of the Term Sheet and
these Standard Terms and Conditions. After the Grant Date, subject to termination or
acceleration as provided in these Standard Terms and Conditions and the Plan, the Award shall
become vested as described in the Term Sheet with respect to that number of restricted stock
units as set forth in the Term Sheet; provided that (except as set forth in Section 5 below)
the Participant does not experience a Termination of employment (as defined in the Plan)
prior to the applicable vesting date. Each date on which restricted stock units subject to
the Award vest is referred to herein as a Vesting Date. Notwithstanding anything herein or
in the Term Sheet to the contrary, if a Vesting Date is not a business day, the applicable
portion of the Award shall vest on the next following business day. Restricted stock units
granted under the Award that have vested and are no longer subject to forfeiture are referred
to herein as Vested Units. Restricted stock units granted under the Award that are not
vested and remain subject to forfeiture are referred to herein as Unvested Units. The
vesting period of an Award may be adjusted by the Administrator to reflect the decreased
level of employment during any period in which the Participant is on an approved leave of
absence or is employed on a less than full time basis, provided that the Administrator may
take into consideration any accounting consequences to the Company in making any such
adjustment.3.
    
    SETTLEMENT OF RESTRICTED STOCK UNITSEach Vested Unit will be settled by the delivery of one share of Common Stock (subject to
adjustment under Section 12 of the Plan) to the Participant or, in the event of the
Participants death, to the Participants estate, heir or beneficiary, within 60 days
following the applicable Vesting Date. The issuance of the shares of Common Stock hereunder
may be affected by the issuance of a stock certificate, recording shares on the stock records
of the Company or by crediting shares in an account established on the Participants behalf
with a brokerage firm or other custodian, in each case as determined by the Company.
Fractional shares will not be issued pursuant to the Award.Notwithstanding the above, (i) for administrative or other reasons, the Company may from time
to time temporarily suspend the issuance of shares of Common Stock in respect of Vested
Units, (ii) the Company shall not be obligated to deliver any shares of the Common Stock
during any period when the Company determines that the delivery of shares hereunder would
violate any federal, state or other applicable laws, (iii) the Company may issue shares of
Common Stock hereunder subject to any restrictive legends that, as determined by the
Companys counsel, are necessary to comply with securities or other regulatory requirements,
(iv) the date on which shares are issued hereunder may include a delay in order to provide
the
Company such time as it determines appropriate to address tax withholding and other
administrative matters, and (v) shares shall not be issued or issuable pursuant to this
provision to the extent of any deferral pursuant to a deferred compensation program that the
Company has made available for purposes of allowing deferral of such shares; provided that,
in the case of clauses (i)  (iv), in no event shall the date of delivery be later than the
last date on which settlement may take place without converting this Award into
non-qualified compensation within the meaning of Section 409A of the Internal Revenue Code
of 1986, as amended.




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4.
    
    RIGHTS AS STOCKHOLDERPrior to any issuance of shares of Common Stock in settlement of the Award, no shares of
Common Stock will be reserved or earmarked for the Participant or the Participants account
nor shall the Participant have any of the rights of a stockholder with respect to such
shares. The Participant will not be entitled to any privileges of ownership of the shares of
Common Stock (including, without limitation, any voting or dividend rights) underlying Vested
Units and/or Unvested Units unless and until shares of Common Stock are actually delivered to
the Participant hereunder.5.
    
    TERMINATION OF EMPLOYMENTExcept as provided in this Section 5, all Unvested Units shall be forfeited by the
Participant and cancelled and surrendered to the Company without payment of any consideration
to the Participant upon the date of the Participants Termination of employment (as defined
in the Plan) for any reason.
 A.
    
    Upon the Participants Termination of employment as a result of the death of the
Participant, the Award shall be deemed to have become fully vested immediately prior to
such Termination of employment.
 B.
    
    Upon the Participants Termination of employment as a result of the Total and
Permanent Disablement (as defined in the Plan) of the Participant, the Award shall be
deemed to have become fully vested immediately prior to such Termination of employment.
 C.
    
    Upon the Participants Termination of employment as a result of the Participants
Retirement (as defined in the Plan), the Award shall be deemed to have become fully
vested immediately prior to such Termination of employment.
 D.
    
    If, within one year after a Change in Control (as defined in Section 19 hereof),
the Participant incurs a Termination of employment for any reason other than for Cause
(as defined in Section 19 hereof) or voluntary resignation by the Participant, the Award
shall be deemed to have become fully vested immediately prior to such Termination of
employment.
 6.
    
    RESTRICTIONS ON RESALES OF SHARESThe Company may impose such restrictions, conditions or limitations as it determines
appropriate as to the timing and manner of any re-sales by the Participant or other
subsequent transfers by the Participant of any shares of Common Stock issued in respect of
Vested Units, including without limitation (a) restrictions under an insider trading policy,
(b) restrictions designed to delay and/or coordinate the timing and manner of sales by
Participant and other holders and (c) restrictions as to the use of a specified brokerage
firm for such re-sales or other transfers.7.
    
    INCOME TAXESThe Participant will be subject to federal and state income and other tax withholding
requirements on a date (generally, the Vesting Date) determined by applicable law (any such
date, the Taxable Date), based on the fair market value of the shares of Common Stock
underlying the Vested Units that vest. The Participant will be solely responsible for the
payment of all U.S. federal income and other taxes, including any state, local or non-U.S.
income or employment tax obligation that may be related to the Vested Units, including any
such taxes that are required to be withheld and paid over to the applicable tax
authorities (the Tax Withholding Obligation). The Participant will be responsible for the
satisfaction of such Tax Withholding Obligation in a manner acceptable to the Company in its
sole discretion.
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By accepting the Award the Participant agrees that, unless and to the extent the Participant
has otherwise satisfied the Tax Withholding Obligations in a manner permitted or required by
the Administrator pursuant to the Plan, the Company is authorized to withhold from the shares
of Common Stock issuable to the Participant in respect of Vested Units the whole number of
shares (rounding up) having a value (as determined by the Company consistent with any
applicable tax requirements) on the Taxable Date or the first trading day before the Taxable
Date sufficient to satisfy the applicable Tax Withholding Obligation. If the withheld shares
are not sufficient to satisfy the Participants Tax Withholding Obligation, the Participant
agrees to pay to the Company as soon as practicable any amount of the Tax Withholding
Obligation that is not satisfied by the withholding of shares of Common Stock described above
and if the withheld shares are more than sufficient to satisfy the Participants Tax
Withholding Obligation the Company shall make such arrangement as it determines appropriate
to credit such amount for the Participants benefit.At any time not less than five (5) business days before any Tax Withholding Obligation arises
(e.g., a settlement date), the Participant may elect to satisfy all or any part of the
Participants Tax Withholding Obligation by delivering to the Company an amount that the
Company determines is sufficient (in light of the uncertainty of the exact amount thereof) to
so satisfy the Tax Withholding Obligation by (i) wire transfer to such account as the Company
may direct, (ii) delivery of a certified check payable to the Company, or (iii) such other
means as specified from time to time by the Administrator, in each case unless the Company
has specified prior to such date that the Participant is not permitted to so satisfy the Tax
Withholding Obligation.The Company may refuse to issue any shares of Common Stock to the Participant until the
Participant satisfies the Tax Withholding Obligation. The Participant acknowledges that the
Company has the right to retain without notice from shares issuable under the Award or from
salary or other amounts payable to the Participant, shares or cash having a value sufficient
to satisfy the Tax Withholding Obligation.The Participant is ultimately liable and responsible for all taxes owed by the Participant in
connection with the Award, regardless of any action the Company takes or any transaction
pursuant to this Section 7 with respect to any tax withholding obligations that arise in
connection with the Award. The Company makes no representation or undertaking regarding the
treatment of any tax withholding in connection with the grant, issuance, vesting or
settlement of the Award or the subsequent sale of any of the shares of Common Stock
underlying Vested Units. The Company does not commit and is under no obligation to structure
the Award to reduce or eliminate the Participants tax liability.8.
    
    NON-TRANSFERABILITY OF AWARDUnless otherwise provided by the Administrator, the Participant may not assign, transfer or
pledge the Award, the shares of Common Stock subject thereto or any right or interest therein
to anyone other than by will or the laws of descent and distribution. The Company may cancel
the Participants Award if the Participant attempts to assign or transfer it in a manner
inconsistent with this Section 8.9.
    
    THE PLAN AND OTHER AGREEMENTSIn addition to these Terms and Conditions, the Award shall be subject to the terms of the
Plan, which are incorporated into these Standard Terms and Conditions by this reference.
Certain capitalized terms not otherwise defined herein are defined in the Plan. In the event
of a conflict between the terms and conditions of these Standard Terms and Condition and the
Plan, the Plan controls.The Term Sheet, these Standard Terms and Conditions and the Plan constitute the entire
understanding between the Participant and the Company regarding the Award. Any prior
agreements, commitments or negotiations concerning the Award are superseded.
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10.
    
    LIMITATION OF INTEREST IN SHARES SUBJECT TO AWARDNeither the Participant (individually or as a member of a group) nor any beneficiary or other
person claiming under or through the Participant shall have any right, title, interest, or
privilege in or to any shares of Common Stock allocated or reserved for the purpose of the
Plan or subject to the Term Sheet or these Standard Terms and Conditions except as to such
shares of Common Stock, if any, as shall have been issued to such person in respect of Vested
Units.11.
    
    NOT A CONTRACT FOR EMPLOYMENT.Nothing in the Plan, in the Term Sheet, these Standard Terms and Conditions or any other
instrument executed pursuant to the Plan shall confer upon the Participant any right to
continue in the Companys employ or service nor limit in any way the Companys right to
terminate the Participants employment at any time for any reason.12.
    
    NOTICESAll notices, requests, demands and other communications pursuant to these Standard Terms and
Conditions shall be in writing and shall be deemed to have been duly given if personally
delivered, telexed or telecopied to, or, if mailed, when received by, the other party at the
following addresses (or at such other address as shall be given in writing by either party to
the other):If to the Company to:The Corporate Executive Board Company1919 North Lynn StreetArlington, Virginia 22209Attention: Chief Financial OfficerIf to the Participant, to the address set forth below the Participants signature on the Term
Sheet.13.
    
    SEPARABILITY.In the event that any provision of these Standard Terms and Conditions is declared to be
illegal, invalid or otherwise unenforceable by a court of competent jurisdiction, such
provision shall be reformed, if possible, to the extent necessary to render it legal, valid
and enforceable, or otherwise deleted, and the remainder of these Standard Terms and
Conditions shall not be affected except to the extent necessary to reform or delete such
illegal, invalid or unenforceable provision.14.
    
    HEADINGS.The headings preceding the text of the sections hereof are inserted solely for convenience of
reference, and shall not constitute a part of these Standard Terms and Conditions, nor shall
they affect its meaning, construction or effect.15.
    
    FURTHER ASSURANCES.Each party shall cooperate and take such action as may be reasonably requested by another
party in order to carry out the provisions and purposes of these Standard Terms and
Conditions.16.
    
    BINDING EFFECT.These Standard Terms and Conditions shall inure to the benefit of and be binding upon the
parties hereto and their respective permitted heirs, beneficiaries, successors and assigns.
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17.
    
    DISPUTESAll questions arising under the Plan or under these Standard Terms and Conditions shall be
decided by the Administrator in its total and absolute discretion. In the event the
Participant or other holder of an Award believes that a decision by the Administrator with
respect to such person was arbitrary or capricious, the Participant or other holder may
request arbitration with respect to such decision in accordance with Section 23 of the Plan.
The review by the arbitrator shall be limited to determining whether the Administrators
decision was arbitrary or capricious. This arbitration shall be the sole and exclusive
review permitted of the Administrators decision, and the Participant and any other holder
hereby explicitly waive any right to judicial review.18.
    
    ELECTRONIC DELIVERYThe Company may, in its sole discretion, decide to deliver any documents related to any
awards granted under the Plan by electronic means or to request the Participants consent to
participate in the Plan by electronic means. By accepting the Award, the Participant consents
to receive such documents by electronic delivery and, if requested, to agree to participate
in the Plan through an on-line or electronic system established and maintained by the Company
or another third party designated by the Company, and such consent shall remain in effect
throughout the Participants term of employment or service with the Company and thereafter
until withdrawn in writing by the Participant.19.
    
    DEFINITIONS
  A.
    
    Cause means (i) the commission of an act of fraud or theft against the Company;
(ii) conviction for any felony; (iii) conviction for any misdemeanor involving moral
turpitude which might, in the Companys opinion, cause embarrassment to the Company;
(iv) a significant violation of any material Company policy; (v) willful or repeated
non-performance or substandard performance of material duties which is not cured within
thirty (30) days after written notice thereof to the Participant; or (vi) violation of
any material District of Columbia, state or federal laws, rules or regulations in
connection with or during performance of the Participants work which, if such violation
is curable, is not cured within thirty (30) days after notice thereof to the
Participant.
 B.
    
    Change in Control means the occurrence of any of the following:
 (i)
    
    the acquisition by a person or group (as those terms are used
in Sections 13(d) and 14(d)(2) of the Securities Exchange Act of 1934, as amended
(the Exchange Act), and the rules promulgated thereunder), other than by
Permitted Holders, of beneficial ownership (as defined in Exchange Act Rule
13d-3) directly or indirectly, of any securities of the Company or any successor
of the Company immediately after which such person or group owns securities
representing 50% or more of the combined voting power of the Company or any
successor of the Company;
 (ii)
    
    within any 12-month period, the individuals who were directors of
the Company as of December 31, 2005 (the Incumbent Directors) ceasing for any
reason other than death or disability to constitute at least a majority of the
Board of Directors, provided that any director who was not a director as of
December 31, 2005 shall be deemed to be an Incumbent Director if such director
was appointed or elected to the Board of Directors by, or on the recommendation
or approval of, at least a majority of directors who then qualified as Incumbent
Directors, provided further that any director appointed or elected to the Board
of Directors to avoid or settle a threatened or actual proxy contest shall in no
event be deemed to be an Incumbent Director; or
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(iii)
    
    approval by the stockholders of the Company of any merger,
consolidation or reorganization involving the Company, unless either (A) the
stockholders of the Company immediately before such merger, consolidation or
reorganization own, directly or indirectly immediately following such merger,
consolidation or reorganization, at least 60% of the combined voting power of
the company(ies) resulting from such merger, consolidation or reorganization in
substantially the same proportion as their ownership immediately before such
merger, consolidation or reorganization, or (B) the stockholders of the Company
immediately after such merger, consolidation or reorganization include
Permitted Holders;
 (iv)
    
    approval by the stockholders of the Company of a transfer of 50% or
more of the assets of the Company or a transfer of assets that during the current
or either of the prior two fiscal years accounted for more than 50% of the
Companys revenues or income (for the avoidance of doubt, assets for this
purpose shall exclude cash, cash equivalents and marketable securities), unless
the person to which such transfer is made is either (A) a Subsidiary of the
Company, (B) wholly owned by all of the stockholders of the Company, or
(C) wholly owned by Permitted Holders; or
 (v)
    
    approval by the stockholders of the Company of a complete
liquidation or dissolution of the Company.
 C.
    
    Permitted Holders means:
 (i)
    
    the Company;
 (ii)
    
    any Subsidiary;
 (iii)
    
    any employee benefit plan of the Company or any Subsidiary; and
 (iv)
    
    any group which includes or any person who is wholly or partially
owned by a majority of the individuals who immediately prior to such acquisition
of securities or stockholder approval under paragraphs (i), (iii) or (iv) of the
definition of Change in Control are executive officers (as defined in Exchange
Act Rule 3b-7) of the Company or any successor of the Company; provided that
immediately prior to and for six months following such acquisition of securities
or stockholder approval such executive officers of the Company are beneficial
owners (as defined in Exchange Act Rule 16a-1(a)(2)) of the common stock of the
Company or any successor of the Company; and provided further that such executive
officers employment is not terminated by the Company or any successor of the
Company (other than as a result of death or disability) during the six months
following such acquisition of securities or stockholder approval. A Change of
Control shall be deemed to have occurred on any date within six months following
an acquisition of securities or stockholder approval under paragraphs (i), (iii)
or (iv) of the definition of Change in Control on which any of the conditions set
forth in this clause (iv) cease to be satisfied.
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