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                                                                   EXHIBIT 10.10

                             2001 CBRE HOLDING, INC.
                              STOCK INCENTIVE PLAN

                                OPTION AGREEMENT

             THIS AGREEMENT (the "Agreement"), is made effective as of the
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20/th/ day of July 2001, (the "Date of Grant"), between CBRE Holding, Inc., a
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Delaware corporation (the "Company"), and James H. Leonetti (the "Participant").
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Capitalized terms not otherwise defined herein shall have the same meanings
given them in the 2001 CBRE Holding, Inc. Stock Incentive Plan (the "Plan").

                                R E C I T A L S:
                                - - - - - - - -

             WHEREAS, the Company has adopted the Plan, which Plan is
incorporated herein by reference and made a part of this Agreement; and

             WHEREAS, the Committee has determined that it would be in the best
interests of the Company and its stockholders to grant the Options provided for
herein to the Participant pursuant to the Plan and the terms set forth herein.

             NOW THEREFORE, in consideration of the mutual covenants hereinafter
set forth, the parties agree as follows:

             1.  Grant of the Options. The Company hereby grants to the
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Participant the right and option to purchase, on the terms and conditions
hereinafter set forth, all or any part of an aggregate of 17,186 Shares (the
"Option"), subject to adjustment from time to time pursuant to the Plan. The
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purchase price of the Shares subject to the Option shall be $16.00 per Share,
subject to adjustment from time to time pursuant to the provisions of the Plan.
The Options are intended to be non-qualified stock options, and are not intended
to be treated as options that comply with Section 422 of the Internal Revenue
Code of 1986, as amended.

             2.  Vesting. The portion of the Option which have become vested and
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exercisable at any time as described in this Section 2 are hereinafter referred
to as the "Vested Portion."
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             (a) Vesting Schedule.
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                 (i)  Subject to Section 2(a)(ii) and Section 2(b) below, the
         Option shall vest and become exercisable with respect to 20% of the
         Shares initially subject thereto on the first, second, third, fourth
         and fifth anniversaries of the Date of Grant.

                 (ii) Notwithstanding the foregoing, upon a Change of Control,
         the Option, to the extent not previously canceled pursuant to Section
         2(b) below, shall immediately vest and become exercisable with respect
         to all the Shares at the time subject to the Option.

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             (b)  Termination of Employment.
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             If the Participant's Employment is terminated for any reason, the
Option shall, to the extent not then vested, be canceled by the Company without
consideration. The Vested Portion of the Option shall remain exercisable for the
period set forth in Section 3(a).

             3.   Exercise of Options.
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             (a)  Period of Exercise. Subject to the provisions of the Plan and
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this Agreement, the Participant may exercise all or any part of the Vested
Portion of the Option at any time prior to the earliest to occur of:

                  (i)   the tenth anniversary of the Date of Grant;

                  (ii)  one year following the date of the Participant's
         termination of Employment as a result of death or Disability;

                  (iii) ninety days following the date of the Participant's
         termination of Employment by the Company or applicable Affiliate
         without Cause (other than as a result of death or Disability) or by the
         Participant for any reason; and

                  (iv)  the date of the Participant's termination of Employment
         by the Company or applicable Affiliate for Cause.

             For purposes of this Agreement:

             "Cause" shall mean (i) the Participant's willful failure to perform
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duties to the Company or its Affiliates, which is not cured within 10 days
following written notice from the Company describing such failure, (ii) the
Participant's conviction of a felony, (iii) the Participant's willful
malfeasance or misconduct which is materially and demonstrably injurious to the
Company, or (iv) breach by the Participant of the material terms of any
confidentiality provision to which the Participant is subject.

             "Disability" shall mean the inability of a Participant to perform
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in all material respects his or her duties and responsibilities to the Company,
or its Affiliates, for a period of six consecutive months or for an aggregate of
nine months in any twenty-four consecutive month period by reason of a physical
or mental incapacity. Any question as to the existence of a Disability as to
which the Participant and the Company cannot agree shall be determined in
writing by a qualified independent physician mutually acceptable to the
Participant and the Company. If the Participant and the Company cannot agree as
to a qualified independent physician, each shall appoint such a physician and
those two physicians shall select a third who shall make such determination in
writing. The determination of Disability made in writing to the Company and the
Participant shall be final and conclusive for all purposes of this Agreement.

             "Good Reason" shall mean (i) a substantial diminution in the
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Participant's position or duties, an adverse change in reporting lines, or the
assignment of duties materially inconsistent with his or her position; (ii) any
reduction in the Participant's base salary or material

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adverse change in the Participant's bonus opportunity; or (iii) failure of the
Company to pay compensation or benefits to the Participant when due under any
employment agreement with the Company; in each of the foregoing clauses (i)
through (iii), which is not cured within 30 days following receipt of written
notice from the Participant describing the event that would constitute Good
Reason if not cured within such period.

           (b) Method of Exercise.
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               (i)   Subject to Section 3(a), the Vested Portion of the Options
         may be exercised by delivering to the Company at its principal office
         or its designee written notice of intent to so exercise; provided,
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         that, the Options may be exercised with respect to whole Shares only.
         Such notice shall specify the number of Shares for which the Options
         are being exercised and shall be accompanied by payment in full of the
         Option Price. The purchase price for the Shares as to which Options are
         exercised shall be paid to the Company in full at the time of exercise
         at the election of the Participant (A) in cash or its equivalent (e.g.,
         by check); (B) in Shares having a Fair Market Value equal to the
         aggregate Option Price for the Shares being purchased and satisfying
         such other requirements as may be imposed by the Committee; provided,
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         that such Shares have been held by the Participant for no less than six
         months (or such other period as established from time to time by the
         Committee in order to avoid adverse accounting treatment applying
         generally accepted accounting principles); (C) partly in cash and
         partly in such Shares; or (D) if there should be a public market for
         the Shares at such time, subject to such rules as may be established by
         the Committee, through the delivery of irrevocable instructions to a
         broker to sell Shares obtained upon the exercise of the Option and to
         deliver promptly to the Company an amount out of the proceeds of such
         sale equal to the aggregate Option Price for the Shares being
         purchased. The Participant shall also be required to pay all
         withholding taxes relating to the exercise.

               (ii)  Notwithstanding any other provision of the Plan or this
         Agreement to the contrary, unless there is an available exemption from
         such registration or qualification requirements, the Options may not be
         exercised prior to the completion of any registration or qualification
         of the Options or the Shares that is required to comply with applicable
         state and federal securities laws or any ruling or regulation of any
         governmental body or national securities exchange that the Committee
         shall in its sole discretion determine in good faith to be necessary or
         advisable.

               (iii) Upon the Company's determination that the Options have been
         validly exercised as to any of the Shares, the Company shall issue
         certificates in the Participant's name for such Shares. However, the
         Company shall not be liable to the Participant for damages relating to
         any delays in issuing the certificates to the Participant, any loss of
         the certificates, or any mistakes or errors in the issuance of the
         certificates or in the certificates themselves.

               (iv)  Should the Participant die while holding the Options, the
         Vested Portion of the Options shall remain exercisable by the
         Participant's executor or administrator, or the person or persons to
         whom the Participant's rights under this

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         Agreement shall pass by will or by the laws of descent and distribution
         as the case may be, to the extent set forth in Section 3(a). Any heir
         or legatee of the Participant shall take rights herein granted subject
         to the terms and conditions hereof.

                  (v) As a condition to exercising the Options, the Participant
         shall become a party to the Subscription Agreement.

               4. No Right to Continued Employment. Neither the Plan nor this
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Agreement shall be construed as giving the Participant the right to be retained
in the Employment of the Company or any Affiliate. Further, the Company or an
Affiliate may at any time dismiss the Participant or discontinue any Employment,
free from any liability or any claim under the Plan or this Agreement, except as
otherwise expressly provided herein.

               5. Legend on Certificates. To the extent provided by the
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Subscription Agreement, the certificates representing the Shares purchased by
exercise of the Options shall contain a legend stating that they are subject to
the Subscription Agreement and may be subject to such stop transfer orders and
other restrictions as the Committee may deem advisable under the Plan or the
rules, regulations and other requirements of the Securities and Exchange
Commission, any stock exchange upon which such Shares are listed, and any
applicable Federal or state laws, and the Committee may cause an additional
legend or legends to be put on any such certificates to make appropriate
reference to such other restrictions.

               6. Transferability. Except as otherwise permitted by the
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Committee, the Options are exercisable only by the Participant during the
Participant's lifetime and may not be assigned, alienated, pledged, attached,
sold or otherwise transferred or encumbered by the Participant otherwise than by
will or by the laws of descent and distribution, and any such purported
assignment, alienation, pledge, attachment, sale, transfer or encumbrance shall
be void and unenforceable against the Company or any Affiliate; provided, that
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the designation of a beneficiary shall not constitute an assignment, alienation,
pledge, attachment, sale, transfer or encumbrance.

               7. Withholding and Other Taxes. A Participant shall be required
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to pay to the Company or any Affiliate and the Company shall have the right and
is hereby authorized to withhold, any applicable withholding and other taxes in
respect of the Options, their exercise or any payment or transfer under the
Options or under the Plan and to take such other action as may be necessary in
the opinion of the Company to satisfy all obligations for the payment of such
withholding and other taxes (which include, without limitation, income tax and
national insurance contributions payable under the United Kingdom PAYE regime).

               8. Securities Laws. Upon the acquisition of any Shares pursuant
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to the exercise of the Options, the Participant will make or enter into such
written representations, warranties and agreements as the Committee may
reasonably request in order to comply with applicable securities laws or with
this Agreement.

               9. Notices. Any notice necessary under this Agreement shall be
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addressed to the Company in care of its Secretary at the principal executive
office of the Company and to the



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Participant at the address appearing in the personnel records of the Company for
the Participant or to either party at such other address as either party hereto
may hereafter designate in writing to the other. Any such notice shall be deemed
effective upon receipt thereof by the addressee.

            10. Choice of Law. THE INTERPRETATION, PERFORMANCE AND ENFORCEMENT
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OF THIS AGREEMENT SHALL BE GOVERNED BY THE LAWS OF THE STATE OF DELAWARE.

            11. Options Subject to Plan and Subscription Agreement. By entering
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into this Agreement the Participant agrees and acknowledges that the Participant
has received a copy of the Plan and the Subscription Agreement. The Options are
subject to the Plan and the Subscription Agreement. The terms and provisions of
the Subscription Agreement as it may be amended from time to time in accordance
with its respective terms are hereby incorporated herein by reference. In the
event of a conflict between any term or provision contained herein and a term or
provision of the Plan or the Subscription Agreement, the applicable terms and
provisions of the Plan or the Subscription Agreement, as applicable, will govern
and prevail. In the event of a conflict between any term or provision of the
Plan and any term or provision of the Subscription Agreement, the applicable
terms and provisions of the Subscription Agreement will govern and prevail.

            12. Signature in Counterparts. This Agreement may be signed in
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counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.





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      IN WITNESS WHEREOF, the parties hereto have executed this Agreement.

                                                CBRE HOLDING, INC.


                                                By:  /s/ Walter V. Stafford
                                                    ------------------------

Agreed and acknowledged as
of the date first above written:


  /s/ James H. Leonetti
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