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                                                                   Exhibit 10.10
                              AMENDED AND RESTATED

                              SHAREHOLDER AGREEMENT

                                       FOR

                       HINES-SUMISEI NY CORE OFFICE TRUST

         This Amended and Restated Shareholder Agreement (this "Agreement") is
entered into as of December 23, 2003, by and among General Motors Investment
Management Corporation, a Delaware corporation, First Plaza Group Trust, a New
York Trust, GMAM Core Plus II-NYC-DC, LLC, a Delaware limited liability company,
[-- --], Hines US Core Office Capital Associates III Limited Partnership, a
Texas limited partnership, Hines-Sumisei U.S. Core Office Fund, L.P., a Delaware
limited partnership and Hines-Sumisei NY Core Office Trust, a Maryland real
estate investment trust.

         This Agreement amends and restates the shareholders agreement
originally entered into by the parties hereto as of August 19, 2003 (the
"Original Agreement"), to correct certain technical deficiency therein and sets
forth the parties' agreement with respect to the voting and ownership of shares
of beneficial interest held by them in Hines-Sumisei NY Core Office Trust.

         In consideration of the terms and conditions set forth herein, the
mutual benefits to be gained by the performance thereof and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree that the Original Agreement is hereby amended
and restated in its entirety as follows:

                                   ARTICLE I

                                   DEFINITIONS

         SECTION 1.1 Defined Terms. As used in this Agreement, the following
terms have the meanings indicated:

         "Agreement": As defined in the Preamble.

         "Affiliate": With respect to any Person, a Person which, directly or
indirectly, Controls, is Controlled by or is under common Control with such
Person; provided, that, for purposes of this Agreement, (i) Holding Partnership
and Persons Controlled by Holding Partnership shall be deemed not to be
Affiliates of HILP, and HILP and Persons Controlled by HILP shall be deemed not
to be Affiliates of Holding Partnership, and (ii) each of the parties to this
Agreement shall be deemed not to be an Affiliate of the Trust or of any Person
Controlled by the Trust.

         "Appraised Value": As defined in Section 3.2(a).

         "Beneficial Owner": A beneficial owner within the meaning of Rules
13d-3 and 13d-5 under the Securities Exchange Act of 1934, as amended, as
interpreted by the Securities

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and Exchange Commission. "Beneficially Own" and "Beneficial Ownership" have
correlative meanings.

         "Board": The Board of Trustees of the Trust.

         "Board Designees": HP Designees, GM Designees, Hines Designees, SLR
Designees and any Replacement Designee, as applicable.

         "Business Day": Any day other than a Saturday or Sunday, that is
neither a legal holiday nor a day on which banking institutions in New York City
are authorized or required by law, regulation or executive order to close.

         "Bylaws": The Bylaws of the Trust, as amended from time to time.

         "Class C Preferred Shares": As defined in Declaration of Trust.

         "Class C Redemption": The redemption of all outstanding Class C Shares
pursuant to Section 6.8 of the Declaration of Trust.

         "Common Shares": As defined in the Declaration of Trust.

         "Control": With respect to any Person, the possession, directly or
indirectly, of the power to direct or cause the direction of the management and
policies of such Person, whether through the ownership of voting securities, by
contract or otherwise.

         "CPII": GMAM Core Plus II-NYC-DC, LLC, a Delaware limited liability
company, and its successors.

         "CPII Designee": A person designated for election to the Board by CPII
pursuant to Section 2.2(a)(iii).

         "Declaration of Trust": The Declaration of Trust of the Trust, as
amended from time to time.

         "Fair Market Value": As defined in Section 3.2(a).

         "Finding of Cause": As defined in Section 2.2(c).

         "GM Designee": A person designated for election to the Board by GMIMCo
pursuant to Section 2.2(a)(ii).

         "GM Group": GMIMCo and any Person Controlled by GMIMCo.

         "GM Investors": As defined in the Investor Rights Agreement.

         "GMIMCo": General Motors Investment Management Corporation, a Delaware
corporation.

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         "HILP": Hines Interests Limited Partnership, a Delaware limited
partnership, and its successors.

         "Hines Control Conditions": As defined in Section 2.2(d).

         "Hines Controlled Entity": Any partnership, limited liability company,
corporation, trust or other entity which is, directly or indirectly, Controlled
by (a) HILP and/or (b) Jeffrey C. Hines and/or Gerald D. Hines or, in the event
of the death or disability of Jeffrey C. Hines and/or Gerald D. Hines, the
heirs, legal representatives or estates of either or both of them.

         "Hines Designees": HP Designees who are employees or agents of HILP.

         "Hines Group": HILP, Gerald D. Hines, Jeffrey C. Hines, the estates,
spouses, children and grandchildren of Gerald D. Hines and Jeffrey C. Hines,
present and former employees of HILP, and any trust for the benefit of any of
the foregoing.

         "Hines Investor": Hines US Core Office Capital Associates III Limited
Partnership, a Texas limited partnership, and its successors and any Hines
Controlled Entity to which Hines Investor Transfers any Shares in accordance
with the terms of this Agreement.

         "hold": With respect to any Shares, to be (i) the record holder of such
Shares as shown on the books and records of the Trust, or (ii) the Beneficial
Owner of such Shares. The terms "held" and "holder" have correlative meanings.

         "Holding Partnership": Hines-Sumisei U.S. Core Office Fund, L.P., a
Delaware limited partnership, and its successors.

         "Holding Partnership Agreement": The Agreement of Limited Partnership
of Holding Partnership, as amended from time to time.

         "HP Designee": Any person designated for election to the Board by
Holding Partnership pursuant to Section 2.2(a)(i), including each Hines Designee
and each SLR Designee.

         "HP General Partner": The general partner of Holding Partnership;
provided, that if Holding Partnership admits a non-managing general partner as
contemplated by the Holding Partnership Agreement, then "HP General Partner"
shall mean the managing general partner of Holding Partnership contemplated by
the Holding Partnership Agreement.

         "Investor Rights Agreement": The Amended and Restated Investor Rights
Agreement, dated as of December 23, 2003, among the parties hereto (other than
the Hines Investor) and HILP, as such agreement may be amended from time to
time.

         "Majority Shareholder Vote" A vote by holders of more than 50% of the
total voting power of all outstanding Shares.

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         "Master Agreement": As defined in the Organization Agreement.

         "Officer": An Officer of the Trust.

         "Organization Agreement": The Amended and Restated Organization
Agreement for the Hines-Sumisei NY Core Office Trust, dated as of December 23,
2003, among the parties hereto and HILP, as such agreement may be amended from
time to time.

         "Original Agreement": As defined in the Recitals.

         "Party": Each Person who is a party to this Agreement that is a
Shareholder or otherwise has the power to vote or grant consent with respect to
any Shares.

         "Person": An individual, corporation, partnership, limited liability
company, estate, trust, association, joint stock company or other legal entity.

         "Preferred Shares": As defined in the Declaration of Trust.

         "Prime Rate": As defined in Section 3.2(b).

         "Projected Net Proceeds": As defined in Section 3.2(a).

         "Promote Shares": As defined in Section 3.2(a).

         "Removal Date": As defined in Section 3.2(a).

         "Replacement Designee": As defined in Section 2.2(a)(iv).

         "Shareholder": A record holder of Shares.

         "Shares": As defined in the Declaration of Trust.

         "SLR": Sumitomo Life Realty (N.Y.), Inc., a New York corporation, and
its successors.

         "SLR Designees": HP Designees who are employees of or agents of SLR.

         "Transaction Agreements": This Agreement, the Organization Agreement
and the Investor Rights Agreement.

         "Transfer": As to any Shares, to sell, or in any other way directly or
indirectly transfer, assign, distribute, pledge, encumber or otherwise dispose
of, either voluntarily or involuntarily.

         "Trust": Hines-Sumisei NY Core Office Trust, a Maryland real estate
investment trust, and its successors.

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         SECTION 1.2 Interpretation; Terms Generally. The definitions set forth
in Section 1.1 and elsewhere in this Agreement shall apply equally to both the
singular and plural forms of the terms defined. Whenever the context may
require, any pronoun shall include the corresponding masculine, feminine and
neuter forms. Unless otherwise indicated, the words "include", "includes" and
"including" shall be deemed to be followed by the phrase "without limitation."
The words "herein", "hereof" and "hereunder" and words of similar import shall
be deemed to refer to this Agreement in its entirety and not to any part hereof,
unless the context shall otherwise require. All references herein to Articles,
Sections and Schedules shall be deemed to refer to Articles and Sections of and
Schedules to this Agreement, unless the context shall otherwise require. Unless
the context shall otherwise require, any references to any agreement or other
instrument or statute or regulation are to it as amended and supplemented from
time to time (and, in the case of a statute or regulation, to any corresponding
provisions of successor statutes or regulations). Any reference in this
Agreement to a "day" or number of "days" (that does not refer explicitly to a
"Business Day" or "Business Days") shall be interpreted as a reference to a
calendar day or number of calendar days. If any action or notice is to be taken
or given on or by a particular calendar day, and such calendar day is not a
Business Day, then such action or notice shall be deferred until, or may be
taken or given on, the next Business Day.

                                   ARTICLE II

                                VOTING OF SHARES

         SECTION 2.1 Voting Generally. When any action is required to be taken
by a Party pursuant to this Agreement, such Party shall take all steps
reasonably necessary to implement such action including, without limitation,
voting at any meeting of Shareholders all Shares held by such Party and entitled
to vote at such meeting in favor of such action and/or executing or causing to
be executed, as promptly as practicable, a consent in writing to the taking of
such action. Any agreement by a Party to vote any Shares held by such Party in a
certain manner shall be deemed, in each instance, to include an agreement by
such Party to use its commercially reasonable efforts to take all actions
necessary to call, or to cause the Trust and the appropriate Trustees and
officers of the Trust to call, as promptly as practicable, a special or annual
meeting of Shareholders to consider such action (and such Party shall attend any
such annual or special meeting in person or by proxy), or to cause a written
consent to the taking of such action to be circulated among the Shareholders
(and to execute and deliver any such consent to such action). Each Party further
agrees to vote all of its Shares entitled to vote, and to take all other actions
necessary, to ensure that the Declaration of Trust and Bylaws facilitate and do
not at any time prohibit the actions contemplated by this Agreement.

         SECTION 2.2 Board of Trustees. The Trust shall be managed by a Board of
Trustees having at least nine members. Prior to the Class C Redemption, two
members of the Board shall be elected by the holders of Class C Preferred Shares
pursuant to Section 6.3(a)(ii) of the Declaration of Trust. All other members of
the Board shall be designated and elected as provided in this Section 2.2. The
initial members of the Board of Trustees and the Person which elected or
designated each such member are set forth on Schedule 2.2.

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         (a)      Designation.

                  (i)      HP Designees. For as long as the Hines Control
         Conditions are met, (A) Holding Partnership shall be entitled to
         designate a majority of the Board of Trustees, (B) there shall at all
         times be at least five HP Designees, at least five of whom shall be
         employees or agents of HILP, and (C) notwithstanding clause (B) of this
         sentence, after the Class C Redemption, for as long as Holding
         Partnership is obligated to designate employees or agents of SLR for
         election to the Board pursuant to the terms of the Holding Partnership
         Agreement or the Master Agreement, there shall be at least seven HP
         Designees, at least five of whom shall be employees or agents of HILP
         and two of whom shall be employees or agents of SLR. If at any time the
         Hines Control Conditions are not met, then Holding Partnership shall
         not be entitled to designate a majority of the Board but (1) after the
         Class C Redemption, for as long as Holding Partnership is obligated to
         designate employees or agents of SLR for election to the Board pursuant
         to the terms of the Holding Partnership Agreement or the Master
         Agreement, Holding Partnership shall be entitled to designate two SLR
         Designees for election to the Board, and (2) for as long as Holding
         Partnership Beneficially Owns at least 20% of the outstanding Shares,
         Holding Partnership shall be entitled to designate one HP Designee for
         election to the Board in addition to the two SLR Designees designated
         pursuant to clause (1) of this sentence.

                  (ii)     GM Designee. For as long as one or more GM Investors
         Beneficially Own at least 20% of the outstanding Shares, GMIMCo shall
         be entitled to designate one member of the Board of Trustees, which
         designee shall be an employee or agent of GMIMCo.

                  (iii)    CPII Designee. For as long as CPII Beneficially Owns
         at least 20% of the Shares acquired by it pursuant to the Organization
         Agreement, CPII shall be entitled to designate one member of the Board
         of Trustees, which designee shall be an employee or agent of GMIMCO.

                  (iv)     Vacancies. If any Board Designee shall be elected or
         appointed as a member of the Board but shall thereafter cease to serve
         as a member of the Board (whether as a result of his or her death or
         resignation or for any other reason) prior to the expiration of his or
         her term of office, the Person who designated such Board Designee shall
         (to the extent such person remains entitled to designate Board
         Designees pursuant to clause (i), (ii) or (iii) of this Section 2.2(a))
         have the right to designate another person (a "Replacement Designee")
         to fill the resulting vacancy in the Board; provided, that, Holding
         Partnership may replace a Hines Designee only with an employee or agent
         of HILP, and GMIMCo and CPII may replace a GM Designee or a CPII
         Designee, respectively, only with an employee or agent of GMIMCo;
         provided further that, a vacancy created by the removal of any Hines
         Designee pursuant to Section 2.2(c) or 2.2(d) shall be filled by the
         Shareholders pursuant to a Majority Shareholder Vote or by Holding
         Partnership pursuant to clause (2) of the second sentence of Section
         2.2(a)(i)as

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         applicable, (in which case, Holding Partnership may replace a
         removed Hines Designee with a person that is not an employee or agent
         of HILP).

         (b)      Trust Action. The Trust shall use its best efforts and take
all action within its power to cause each Board Designee to be elected or
appointed to serve as a member of the Board as promptly as practicable after the
date upon which he or she has been so designated. Without limiting the
generality of the foregoing, the Trust shall take any of the following actions
if required in order to effect the election or appointment of a Board Designee:

                  (i)      If there exists a vacancy on the Board, the Trust
         shall take all necessary action within its power to cause such vacancy
         to be filled through the appointment of such Board Designee.

                  (ii)     If the Board is authorized by law to increase the
         number of members of the Board without approval of the Shareholders,
         the Trust shall take all necessary action within its power to increase
         the size of the Board and cause each newly created trusteeship to be
         filled by the appointment of a Board Designee.

                  (iii)    The Trust shall nominate such Board Designee for
         election as a member of the Board at the next meeting of the
         Shareholders at which members of the Board are to be elected and, in
         connection therewith, shall recommend to the Shareholders the election
         of such Board Designee and vote in favor of such Board Designee all
         legally effective proxies received from Shareholders that authorize or
         direct any officer or Trustee, as proxy holder, to vote in the election
         of Trustees for such Board Designee or which grant to any officer or
         Trustee the power to exercise his or her discretion in voting in the
         election of Trustees.

         (c)      Removal for Cause. Any Trustee may be removed by the
Shareholders by a Majority Shareholder Vote, and the Shareholders may, by a
Majority Shareholder Vote, require the removal of any Officer, if a Finding of
Cause with respect to such Trustee or Officer shall have been made and shall
have become effective and shall not have been withdrawn or rescinded in
accordance with the provisions of this Section 2.2(c). For purposes of this
Agreement, the term "Finding of Cause" means (i) a written determination by the
Shareholders by a Majority Shareholder Vote that a Trustee or Officer has
committed (A) willful malfeasance in the performance of any of such Trustee's or
Officer's material duties in his or her capacity as such (B) willful misconduct
or fraud or (C) gross negligence which is the primary cause of a material
adverse effect on the Trust, which written determination identifies with
reasonable particularity the actions by such Trustee or Officer constituting
such willful malfeasance, willful misconduct, fraud or gross negligence, and, in
the case of gross negligence, the material adverse effect on the Trust resulting
therefrom, and (ii) in the case of gross negligence, the material adverse effect
resulting therefrom has continued without being substantially cured for a period
of at least thirty Business Days after the date upon which such written
determination was given to the Board and such Trustee or Officer; provided,
however, that, (1) at least 10 days prior to submitting any such written
determination, GMIMCo and the GM Investors shall consult with the President of
the Trust and the senior most employee of HILP that is a Hines Designee
regarding the

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circumstances deemed by GMIMCo and the GM Investors to be a possible basis for a
Finding of Cause, and (2) any such Trustee or Officer shall have the right to
dispute any determination that such willful malfeasance, willful misconduct,
fraud or gross negligence has occurred and, in the case of gross negligence,
that such gross negligence is the primary cause of a material adverse effect on
the Trust that has not been substantially cured, and, if such Trustee or Officer
commences legal action for declaratory or injunctive relief with respect to such
Finding of Cause within 15 Business Days after written determination of such is
delivered to the Trust and such Trustee or Officer (which 15 Business Days may,
in the case of gross negligence, be extended for an additional 30 Business Days
if such Officer or Trustee is diligently prosecuting a cure of such gross
negligence), then the applicable Finding of Cause shall not become effective
until the date upon which the dispute with respect to such determination has
been resolved (whether by agreement among such Trustee or Officer, the Trust and
the Shareholders by a Majority Shareholder Vote or as a result of a judgment or
award in the judicial proceeding filed by such Officer or Trustee). Any
determination by the Shareholders, and the effectiveness, of any Finding of
Cause, may be rescinded or withdrawn at any time by the Shareholders by a
Majority Shareholder Vote.

         (d)      Hines Control Conditions. The "Hines Control Conditions" shall
be met as long as all of the following conditions are met:

                  (i)      No Hines Designee or Officer that is an employee of
         HILP has been removed from office pursuant to a Finding of Cause in
         accordance with Section 2.2(c);

                  (ii)     The HP General Partner is a Hines Controlled Entity;

                  (iii)    Neither Hines Investor nor Holding Partnership
         defaults in its obligation to make any capital contribution required to
         be made by it to the Trust under terms of the Organization Agreement,
         which default is not cured within 10 Business Days after notice
         thereof; and

                  (iv)     The Hines Group Beneficially Owns at least 1% of the
         outstanding Shares.

         If at any time the Hines Control Conditions are not met, then (i) the
Shareholders may, by Majority Shareholder Vote, remove all Hines Designees from
office and require the removal of all employees of HILP as Officers of the
Trust, and (ii) each vacancy created by such removal (in the case of Trustees)
shall be filled by a person designated by the Shareholders by Majority
Shareholder Vote, subject to the right of Holding Partnership to designate an HP
Designee pursuant to clause (2) of the second sentence of Section 2.2(a)(i).
Notwithstanding the foregoing, if the Hines Control Condition described in
clause (iv) of this Section 2.2(d) fails to be met as a result of dilution, in
connection with transfers due to admission of new partners to the Holding
Partnership or of new shareholders to the Trust, then the Hines Control
Conditions shall nonetheless be deemed to be met so long as the Hines Group's
Beneficial Ownership of Shares is restored to at least 1% of the outstanding
Shares as soon as practicable after Holding Partnership or Hines Investor
becomes aware of such condition. If any Hines Designees or

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Officers who are employees or agents of HILP are required to be removed from
office pursuant to this Section 2.2(d), the Trust shall use its best efforts to
cause such removal, and to cause the vacancies created by such removal to be
filled in accordance with the applicable provisions of this Section 2.2, as
promptly as practical following the Majority Shareholder Vote requiring such
removal.

         (c)      Observer Rights.

                  (i)      At any time Holding Partnership is entitled to
         designate a Board Designee pursuant to the second sentence of Section
         2.2(a)(i) and no HP Designee other than the SLR Designees is a member
         of the Board, then Holding Partnership shall be entitled to have one
         observer attend each meeting of the Board.

                  (ii)     At any time GMIMCo is entitled to designate a Board
         Designee pursuant to Section 2.2(a)(ii) and no GM Designee is a member
         of the Board, then GMIMCo shall be entitled to have one observer attend
         each meeting of the Board.

                  (iii)    At any time CPII is entitled to designate a Board
         Designee pursuant to Section 2.2(a)(iii) and no CPII Designee is a
         member of the Board, then CPII shall be entitled to have one observer
         attend each meeting of the Board.

                  (iv)     At any time Holding Partnership is entitled to
         designate an SLR Designee pursuant to Section 2.2(a)(i) and no SLR
         Designee is a member of the Board, then, in addition to any other
         observer or HP Designee Holding Partnership is entitled to designate,
         Holding Partnership shall be entitled to have one observer who is an
         employee or agent of SLR attend each meeting of the Board.

                  (v)      The Trust shall send to any Party entitled to
         designate an observer pursuant to clause (i), (ii), (iii) or (iv) of
         this Section 2.2(e) and its designated observer the notice of the time
         and place of any meeting of the Board, and of any written consent being
         solicited from the Board, in the same manner and at the same time as
         notice is sent to the members of the Board. The Trust shall also
         provide to each such party copies of all notices, reports, minutes,
         consents and other documents at the time and in the manner as they are
         provided to the Board.

                  (vi)     Any observer who attends any meetings of the Board,
         as a condition to his or her right to attend such meeting, shall
         execute and comply with an agreement with the Trust containing such
         restrictions on the use and disclosure of confidential information and
         other matters as the Trust may reasonably request.

         SECTION 2.3 Shareholder Action.

         (a)      Except as otherwise provided in subsections (b), (c), (d), (e)
and (f) of this Section 2.3, as to any proposal properly brought before the
Shareholders for a vote or consent in accordance with the Bylaws and the
Declaration of Trust, each Party may vote, or give its

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consent with respect to, all Shares entitled to vote held by such Party for or
against such proposal as such Party may determine in its sole and absolute
discretion.

         (b)      Each Party shall vote all Shares held by it entitled to vote
for the election of Trustees at any meeting of Shareholders called for the
election of Trustees, and shall give its consent with respect to all such Shares
held by it in response to any solicitation of Shareholder consents to the
election of Trustees, in favor of the election to the Board of any Board
Designee nominated by a Party for election to the Board in accordance with
Section 2.2(a) that is the subject of such vote or consent. In addition, except
for a proposal to remove a Trustee made in accordance with Section 2.2(c) or
Section 2.2(d), each Party shall vote all Shares entitled to vote held by it
against any resolution which may be proposed to remove any Board Designee that
is serving as a member of the Board, unless the Person that designated such
Board Designee otherwise requests in writing.

         (c)      For so long as a majority of the Board is composed of Hines
Designees, each Party shall vote, or give its consent with respect to, all
Shares entitled to vote held by such Party for or against any proposal brought
before the Shareholders for their vote or consent with respect to a merger or
consolidation of the Trust, or the sale or disposition of substantially all of
the Trust's assets, pursuant to which the consideration to be received by
Shareholders consists solely of cash, in the manner the Board recommends that
the Shareholders vote with respect to such proposal.

         (d)      Notwithstanding subsection (c) of this Section 2.3, but
subject to subsection (e) of this Section 2.3, as to any vote or consent which,
under the terms of the Declaration of Trust, is required to be obtained from any
class or classes of Shares voting as a separate class, the holders of such class
or classes of Shares may vote, or give their consent with respect to, such
Shares in such separate class vote in any manner they may elect in their sole
and absolute discretion.

         (e)      Notwithstanding anything in this Agreement or any other
Transaction Agreement to the contrary, no Party shall, without the prior written
consent of Hines Investor, vote any Shares held by it in favor of

                  (i)      the authorization of any additional Shares or any
         additional classes or series of Shares; or

                  (ii)     the issuance of any Shares, or securities of the
         Trust that are convertible into, exchangeable for or evidence the right
         to purchase Shares, other than the Shares required or permitted to be
         issued under the terms of the Organization Agreement.

         (f)      Notwithstanding subsection (a) of this Section 2.3, if the
approval of Shareholders is required in order for the Trust to take any action
required to be taken by the Trust under the terms of this Agreement or any other
Transaction Agreement, then each Party shall vote or give its consent with
respect to all Shares entitled to vote held by it in favor of such action. Each
Party hereby consents to the Trust taking any action which it is required to
take under the terms of this Agreement or any other Transaction Agreement.

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                                  ARTICLE III

                          SHARE OWNERSHIP AND TRANSFER

         SECTION 3.1 Conditions to Transfer. In addition to any restrictions
imposed by the Organization Agreement or the Declaration of Trust, it shall be a
condition to any Transfer of Shares by any Party that the applicable Transferee
becomes, pursuant to a written instrument reasonably acceptable to the Trust, a
party to this Agreement bound by the provisions of this Agreement applicable to
the Transferor. No such Transferee shall, without the consent of the other
parties hereto, be entitled to any benefits under this Agreement, unless such
Transferee is (i) a party to this Agreement entitled to the benefits hereof
prior to such Transfer, (ii) a member of the GM Group, in the case of any
Transfer by a member of the GM Group, or (iii) a Hines Controlled Entity, in the
case of any Transfer by a Hines Controlled Entity or Holding Partnership. Any
Transfer made in violation of this Section 3.1 shall be null and void ab initio,
and the Trust shall not recognize any such Transfer or record it on the books of
the Trust.

         SECTION 3.2 Call on Promote Shares.

         (a)      If the Hines Control Conditions fail to be met, and the
Shareholders by Majority Shareholder Vote elect to remove all Hines Designees
from the Board and require the removal of all employees of HILP as Officers
pursuant to Section 2.2(d), then GMIMCo shall have the right to acquire, or
cause its designee to acquire, from Hines Investor a number of Common Shares
equal to, but not less than, the number of Common Shares issued to Hines
Investor pursuant to the Organization Agreement in excess of the number of
Preferred Shares issued to Hines Investor pursuant to the Organization Agreement
(such excess number of Common Shares, the "Promote Shares") for a purchase price
equal to the Fair Market Value of such Common Shares as of the date (the
"Removal Date") of the Majority Shareholder Vote by which the Hines Designees
and such Officers were removed. In order to exercise such right, GMIMCo must
give written notice to Hines Investor of its election to do so within 10 days
after the Removal Date. The "Fair Market Value" of the Promote Shares, as of any
date, means an amount equal to the product of (x) the number of Promote Shares
and (y) the amount in cash that would be distributed in respect of each Common
Share if, on such date, all assets of the Trust were sold for their Appraised
Value and the Projected Net Proceeds of such sales were distributed to the
Shareholders in accordance with Section 6.6 of the Declaration of Trust. For
purposes hereof, the terms "Projected Net Proceeds" and "Appraised Value" have
the meanings given to such terms in the Investor Rights Agreement; provided,
that Hines Investor shall have the right to require a new appraisal with respect
to any asset to the same extent as GIMIMCo would have such right under Article 5
of the Investor Rights Agreement with respect to any appraisal obtained pursuant
to the Investor Rights Agreement.

         (b)      The closing of the purchase and sale of the Promote Shares
pursuant to this Section 3.2 shall take place within 30 days after the Fair
Market Value of the Promote Shares has been finally determined. At such closing,
Hines Investor shall deliver the Promote Shares to GMIMCo or its designee free
and clear of any liens or encumbrances, other than such liens and encumbrances
as are created by the Declaration of Trust, any of the Transaction Agreements or
GMIMCo or any of its Affiliates, in exchange for an amount in cash equal to the

                                      -11-
<PAGE>

Fair Market Value of the Promote Shares or a promissory note from a
credit-worthy entity having a principal face amount equal to the Fair Market
Value of the Promote Shares and a term of not more than three years which bears
interest at the Prime Rate. For purposes hereof, the term "Prime Rate" has the
meaning given to such term in the Investor Rights Agreement.

                                   ARTICLE IV

                               DISTRIBUTION POLICY

         It is the intention of the Shareholders that, subject to the provisions
of the Declaration of Trust and the Investor Rights Agreement, the Trust pay
quarterly dividends in an amount equal to the Trust's net cash flow, less such
amount as the Board of Trustees determines to retain as a reasonable reserve for
contingencies or to fund capital expenditures with respect to the First Closing
Properties (as defined in the Organization Agreement).

                                   ARTICLE V

                                  MISCELLANEOUS

         SECTION 5.1 Entire Agreement. This Agreement and the other Transaction
Agreements constitute the entire agreement among the parties hereto with respect
to the subject matter hereof and supersede any prior agreement or understanding
among or between them with respect to such subject matter.

         SECTION 5.2 Severability. Each provision of this Agreement shall be
considered severable and if for any reason any provision which is not essential
to the effectuation of the basic purposes of this Agreement is determined by a
court of competent jurisdiction to be invalid or unenforceable and contrary to
existing or future applicable law, such invalidity shall not impair the
operation of or affect those provisions of this Agreement which are valid. In
that case, this Agreement shall be construed so as to limit any term or
provision so as to make it enforceable or valid within the requirements of any
applicable law, and in the event such term or provision cannot be so limited,
this Agreement shall be construed to omit such invalid or unenforceable
provisions.

         SECTION 5.3 Notices. All notices, requests, demands and other
communications hereunder shall be in writing and shall be deemed to have been
duly given if (i) mailed, registered mail, first-class postage paid, (ii) sent
by overnight mail or courier, or (iii) delivered by hand, if to any Person, at
such Person's address, or to such Person's facsimile number, as set forth in the
Organization Agreement or as otherwise provided to the other parties hereto in
accordance with this Section 5.3. Any party may change the address to which
notices, requests, demands or other communications under this Agreement are to
be delivered by giving the other parties notice pursuant to this Section 5.3.
Any notice shall be deemed to have been duly given if personally delivered or
sent by the mails or courier or by facsimile confirmed by letter and will be
deemed received, unless earlier received, (i) if sent by certified or registered
mail, return receipt requested, when actually received, (ii) if sent by
overnight mail or courier, when actually received, and (iii) if delivered by
hand, on the date of receipt.

                                      -12-
<PAGE>

         SECTION 5.4 Amendments and Waivers. No amendment to any provisions of
this Agreement shall be valid unless it is in writing and signed by all the
parties hereto. No waiver by any party of any default, misrepresentation or
breach or warranty or covenant hereunder, whether intentional or not, shall be
deemed to extend to any prior or subsequent default, misrepresentation or breach
of warranty or covenant hereunder or affect in any way any rights arising by
virtue of any prior or subsequent occurrence. No waiver shall be effective
hereunder unless contained in a writing signed by the party to be charged with
such waiver.

         SECTION 5.5 Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York.

         SECTION 5.6 Successors and Assigns. This Agreement shall be binding
upon and inure to the benefit of the parties hereto and their legal
representatives, heirs, successors and permitted assigns. No party hereto may
assign any of its rights or obligations hereunder without the consent of the
other parties, except to the extent such assignment is permitted or required in
connection with a Transfer of Shares made in accordance with the provisions of
Article III.

         SECTION 5.7 Construction. Each party hereto acknowledges that is has
been represented by counsel during the negotiation, preparation and execution of
this Agreement and, therefore, waives the application of any law, regulation,
holding or rule of construction providing that ambiguities in an agreement or
document will be construed against the party drafting such agreement or
document.

         SECTION 5.8 Headings. The Article and Section headings in this
Agreement are for convenience of reference only, and shall not be deemed to
alter or affect the meaning or interpretation of any provisions hereof.

         SECTION 5.9 No Third Party Beneficiaries. Nothing in this Agreement,
expressly or implied, is intended to confer upon any Person other than the
parties hereto or their respective successors and permitted assigns any rights,
benefits, remedies, obligations or liabilities under this Agreement.

         SECTION 5.10 Counterparts. This Agreement may be executed in one or
more counterparts, each of which shall be deemed an original, but all of which,
when taken together, shall constitute one and the same instrument.

                            [Signature Pages Follow]

                                      -13-
<PAGE>
         IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed and delivered as of the date first set forth above.

                                       HINES-SUMISEI U.S. CORE OFFICE FUND, L.P.

                                       By: Hines US Core Office Capital LLC

                                         By: Hines Interests Limited Partnership

                                           By: Hines Holdings, Inc.

                                             By: /s/ CHARLES M. BAUGHN
                                                 -------------------------------
                                                 Charlie M. Baughn
                                                 Executive Vice President

                                       HINES-SUMISEI NY CORE OFFICE TRUST

                                       By: /s/ JAMES A. HIME
                                           -------------------------------------
                                           James A. Hime
                                           President

                                       HINES US CORE OFFICE CAPITAL
                                       ASSOCIATES III LIMITED PARTNERSHIP

                                         By: Hines Interests Limited Partnership

                                           By: Hines Holdings, Inc.

                                             By: /s/ CHARLES M. BAUGHN
                                                 -------------------------------
                                                 Charles M. Baughn
                                                 Executive Vice President.


<PAGE>
                                      GENERAL MOTORS INVESTMENT
                                      MANAGEMENT CORPORATION

                                      By: /s/ Thomas E. Dobrowski
                                          -------------------------------------
                                          Name: Thomas E. Dobrowski
                                          Title: Managing Director

                                      FIRST PLAZA GROUP TRUST

                                      By: JP Morgan Chase Bank, as Trustee for
                                          First Plaza Group Trust

                                      By: /s/ John A. Ferrante
                                          -------------------------------------
                                          Name: John A. Ferrante
                                          Title: Assistant Treasurer

                                      GMAM CORE PLUS II-NYC-DC, LLC

                                      By: General Motors Investment Management
                                      Corporation, as its Manager

                                      By: /s/ Thomas E. Dobrowski
                                          -------------------------------------
                                          Name: Thomas E. Dobrowski
                                          Title: Managing Director

                                      [-- --]

                                      By: [-- --]


                                      By: [-- --]
                                          -------------------------------------
                                          Name: [-- --]
                                          Title: [-- --]

<PAGE>

                                                                    SCHEDULE 2.2

                            Initial Board of Trustees

<TABLE>
<CAPTION>
     Name                               Elected or Designated By
     ----                               ------------------------
<S>                             <C>
Gerald D. Hines                 Holding Partnership (Hines Designee)
Jeffrey C. Hines                Holding Partnership (Hines Designee)
C. Hastings Johnson             Holding Partnership (Hines Designee)
Charles M. Baughn               Holding Partnership (Hines Designee)
James A. Hime                   Holding Partnership (Hines Designee)
Norio Morimoto                  Holders of Class C Preferred Shares (SLR Designee)
Shinichi Kawanishi              Holders of Class C Preferred Shares (SLR Designee)
Joseph Stecher                  GMIMCo (Designee)
Thomas E. Dobrowski             CPII (CPII Designee)
</TABLE>