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                                                                EXHIBIT 10.1.2

                               FIFTH AMENDMENT TO

                        AGREEMENT OF LIMITED PARTNERSHIP

                                       OF

                        EOP OPERATING LIMITED PARTNERSHIP


          This Fifth Amendment is made as of February 19, 1998 by and among
Equity Office Properties Trust, a Maryland real estate investment trust, as
managing general partner (the "Company" or the "Managing General Partner") of
EOP Operating Limited Partnership, a Delaware limited partnership (the
"Partnership"), and as attorney-in-fact for the Persons named on Exhibit A to
the Agreement of Limited Partnership of EOP Operating Limited Partnership, dated
as of July 3, 1997, as amended, (the "Partnership Agreement") for the purpose of
amending the Partnership Agreement. Capitalized terms used herein and not
defined shall have the meanings given to them in the Partnership Agreement.

          WHEREAS, the Board of Trustees of the Company (the "Board"), by
Unanimous Consent of the Trustees dated February 12, 1998 and by action of the
Pricing Committee of the Board pursuant to delegated authority on February 13,
1998, classified and designated 7,000,000 Preferred Shares (as defined in the
Declaration of Trust of the Company (the "Declaration of Trust")) as Series B
Preferred Shares (as defined below);

          WHEREAS, the Board filed Articles Supplementary to the Declaration of
Trust (the "Articles Supplementary") with the State Department of Assessments
and Taxation of Maryland on February 19, 1998, establishing the series of
preferred shares, designated Series B Preferred Shares;

          WHEREAS, on February 19, 1998, the Company issued 6,000,000 of the
Series B Preferred Shares;

          WHEREAS, the Managing General Partner has determined that, in
connection with the issuance of the Series B Preferred Shares, it is necessary
and desirable to amend the Partnership Agreement to create additional
Partnership Units having designations, preferences and other rights which are
substantially the same as the economic rights of the Series B Preferred Shares.

          NOW, THEREFORE, in consideration of the premises and for other good
and valuable consideration, the receipt and sufficiency of which hereby are
acknowledged, the Managing General Partner hereby amends the Partnership
Agreement as follows:
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          1.  Article I of the Partnership Agreement is hereby amended by adding
the following definitions:

          "Series B Preferred Shares" means the 5.25% Series B Convertible,
Cumulative Preferred Shares of the Company, with the preferences, conversion
and other rights, voting powers, restrictions, limitations as to distributions,
qualifications and terms and conditions of redemption of shares as described in
the Articles Supplementary; and

          "Series B Preferred Units" means the series of Partnership Units
representing units of Limited Partnership Interest designated as the 5.25%
Series B Convertible, Cumulative Preferred Units with the preferences,
conversion and other rights, voting powers, restrictions, limitations as to
distributions, qualifications and terms and conditions of redemption of units as
described herein; and

          2.  In accordance with Section 4.2.A of the Partnership Agreement, set
forth below are the terms and conditions of the Series B Preferred Units hereby
established and issued to the Company in consideration of the Company's
contribution to the Partnership of the net proceeds following the issuance and
sale of the Series B Preferred Shares by the Company:

          A.  Designation and Number. A series of Partnership Units, designated
as Series B Preferred Units, is hereby established. The number of Series B
Preferred Units shall be 6,000,000.

          B.  Rank. The Series B Preferred Units shall, with respect to
distribution rights and rights upon voluntary or involuntary liquidation,
dissolution or winding up of the affairs of the Partnership, rank (a) senior to
the Class A Units, Class B Units and all Partnership Interests ranking junior to
the Series B Preferred Units; (b) on a parity with the Series A Preferred Units
and all other Partnership Interests issued by the Partnership the terms of which
specifically provide that such Partnership Interests rank on a parity with the
Series B Preferred Units; and (c) junior to all Partnership Interests issued by
the Partnership the terms of which specifically provide that such Partnership
Interests rank senior to the Series B Preferred Units.

          C.  Distributions.

          (i) Pursuant to Section 5.1 of the Partnership Agreement, holders of
Series B Preferred Units shall be entitled to receive, out of Available Cash,
cumulative preferential cash distributions at the rate of 5.25% of the $50.00
liquidation preference per annum (equivalent to a fixed annual amount of $2.625
per unit). Distributions (which term as used herein shall include liquidated


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damages, if any, payable pursuant to subsection 2.C.(vi)) on the Series B
Preferred Units shall be payable quarterly and be cumulative from the fifteenth
day of each February, May, August and November or, if not a business day, the
next succeeding business day (each, a "Series B Preferred Unit Distribution
Payment Date"). Any distribution (including the initial distribution) payable on
the Series B Preferred Units for any partial distribution period shall be
prorated and computed on the basis of a 360-day year consisting of twelve 30-day
months.

          (ii) No distribution on the Series B Preferred Units shall be
authorized by the Board or paid or set apart for payment by the Partnership at
such time as the terms and provisions of any agreement of the Partnership,
including any agreement relating to its indebtedness, prohibits such
authorization, payment or setting apart for payment or provides that such
authorization, payment or setting apart for payment would constitute a breach
thereof, or a default thereunder, or if such authorization or payment shall be
restricted or prohibited by law. No interest, or sum of money in lieu of
interest, shall be payable in respect of any distribution payment or payments on
the Series B Preferred Units which may be in arrears.

          Notwithstanding the foregoing, distributions with respect to the
Series B Preferred Units shall accumulate whether or not any of the foregoing
restrictions exist, whether or not there is sufficient Available Cash for the
payment thereof and whether or not such distributions are authorized.
Accumulated but unpaid distributions on the Series B Preferred Units shall not
bear interest and holders of the Series B Preferred Units shall not be entitled
to any distributions in excess of full cumulative distributions. Any
distribution payment made on the Series B Preferred Units shall first be
credited against the earliest accumulated but unpaid distribution due with
respect to such units which remains payable.

          (iii) Except as provided in subsection 2.C.(iv), if any Series B
Preferred Units are outstanding, no distributions (other than in Partnership
Interests ranking junior to the Series B Preferred Units as to distributions and
upon liquidation, dissolution or winding up of the affairs of the Partnership)
shall be declared or paid or set apart for payment nor shall any other
distribution be declared or made upon the Class A Units, the Class B Units, or
any other Partnership Interests ranking junior to or on a parity with the Series
B Preferred Units as to distributions or upon liquidation, dissolution or
winding up of the affairs of the Partnership for any period unless full
cumulative distributions have been or contemporaneously are declared and paid or
declared and a sum sufficient for the payment thereof set apart for such payment
on the Series B Preferred Units for all past distribution periods and the then
current distribution period, nor shall any Class A Units, Class B Units, or any
other Partnership Interests ranking junior to or on a parity with the Series B
Preferred Units as to distributions or upon liquidation, dissolution or winding
up of the affairs of the Partnership, be redeemed, purchased or otherwise
acquired for any consideration (or any moneys be paid to or

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made available for a sinking fund for the redemption of any such Partnership
Interests) by the Partnership (except by conversion into or exchange for
Partnership Interests ranking junior to the Series B Preferred Units as to
distributions and upon liquidation, dissolution or winding up of the affairs of
the Partnership).

          (iv) When distributions are not paid in full (or a sum sufficient for
such full payment is not so set apart) upon the Series B Preferred Units and any
other Partnership Interests ranking on a parity as to distributions with the
Series B Preferred Units, all distributions declared upon the Series B Preferred
Units and any other Partnership Interests ranking on a parity as to
distributions with the Series B Preferred Units shall be declared pro rata so
that the amount of distributions declared per unit of Series B Preferred Units
and such other Partnership Interests shall in all cases bear to each other the
same ratio that accumulated distributions per unit on the Series B Preferred
Units and such other Partnership Interests (which shall not include any
accumulation in respect of unpaid distributions for prior distribution periods
if such other Partnership Interests do not have a cumulative distribution) bear
to each other.

          (v) Holders of Series B Preferred Units shall not be entitled to any
distribution, whether payable in cash, property or Partnership Interests, in
excess of full cumulative distributions on the Series B Preferred Units as
described above. Accumulated but unpaid distributions on the Series B Preferred
Units will accumulate as of the Series B Preferred Unit Distribution Payment
Date on which they first become payable.

          (vi) If the Company fails to file a registration statement within the
period of time required by the Registration Rights Agreement dated February 19,
1998 between the Company and Lehman Brothers Inc. (the "Registration Rights
Agreement"), or the required registration statement does not become effective
within the period of time required by the Registration Rights Agreement, or the
Company fails to maintain the effectiveness of the registration statement as
required by the Registration Rights Agreement, or the Series B Preferred Shares
are not approved for listing by the New York Stock Exchange within the period of
time required by the Registration Rights Agreement, liquidated damages shall
accumulate on the $50.00 liquidation preference of the Series B Preferred Units
at a rate of 0.25% per annum (equivalent to a fixed annual amount of $0.125 per
unit) with respect to the first quarter immediately following such event and at
a rate of 0.50% per annum (equivalent to a fixed annual amount of $0.25 per
unit) with respect to the second quarter and all subsequent quarters following
such event ("Liquidated Damages").

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          D.  Allocations.


          Allocations of the Partnership's items of income, gain, loss and
deduction shall be allocated among holders of Series B Preferred Units in
accordance with Article VI of the Partnership Agreement.

          E.  Liquidation Preference.

          (i) In the event of any voluntary or involuntary liquidation,
dissolution or winding up of the affairs of the Partnership, the holders of the
Series B Preferred Units shall be entitled to receive out of the assets of the
Partnership available for distribution to the Partners pursuant to Section
13.2.A of the Partnership Agreement a liquidation preference of $50.00 per
Series B Preferred Unit, plus an amount equal to any accumulated and unpaid
distributions to the date of payment, before any distribution of assets is made
to holders of Class A Units, Class B Units or any other Partnership Interests
that rank junior to the Series B Preferred Units as to liquidation rights.

         (ii) If upon any such voluntary or involuntary liquidation,
dissolution or winding up of the affairs of the Partnership, the assets of the
Partnership are insufficient to make such full payment to holders of the Series
B Preferred Units and the corresponding amounts payable on all other Partnership
Interests ranking on a parity with the Series B Preferred Units in the
distribution of assets, then the holders of such Partnership Interests shall
share ratably in any such distribution of assets in proportion to the full
liquidating distributions to which they would otherwise be respectively
entitled.

        (iii) After payment of the full amount of the liquidating
distributions to which they are entitled, the holders of Series B Preferred
Units shall have no right or claim to any of the remaining assets of the
Partnership.

         (iv) None of a consolidation or merger of the Partnership with or into
another entity, merger of another entity with or into the Partnership, a
statutory unit exchange by the Partnership or a sale, lease or conveyance of all
or substantially all of the Partnership's property or business shall be
considered a liquidation, dissolution or winding up of the affairs of the
Partnership.

          F.  Redemption.


          In connection with redemption by the Company of any of its Series B
Preferred Shares in accordance with the provisions of the Articles
Supplementary, the Partnership shall provide cash to the Company for such
purpose which shall be equal to the redemption price (as set forth in the
Articles Supplementary) and one Series B Preferred Unit shall be canceled with
respect to each Series B Preferred Share so redeemed by the Company. From and
after the Series B Preferred Share Redemption Date (as defined in the Articles
Supplementary), the Series B Preferred


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Units so canceled shall no longer be outstanding and all rights hereunder, to
distributions or otherwise, with respect to such Series B Preferred Units shall
cease.

          G. Conversion.


          In connection with conversion into common shares of beneficial
interest, $.01 par value per share of the Company ("Common Shares") of any
Series B Preferred Shares in accordance with the provisions of the Articles
Supplementary, the Partnership shall (i) issue to the Company a number of Class
A Units equal to the number of Common Shares issued by the Company upon such
conversion; and (ii) provide cash to the Company, if necessary, in an amount
equal to the amount of cash paid by the Company upon conversion of any Series B
Preferred Shares which would otherwise result in the issuance of fractional
Common Shares. One Series B Preferred Unit, or any fraction thereof, shall be
canceled with respect to each Series B Preferred Share, or any fraction thereof,
so converted, and from and after such conversion, the Series B Preferred Units
so canceled shall no longer be outstanding and all rights hereunder, to
distributions or otherwise, with respect to such Series B Preferred Units shall
cease.

          3. Except as modified herein, all terms and conditions of the
Partnership Agreement shall remain in full force and effect, which terms and
conditions the Managing General Partner hereby ratifies and confirms.

                                    * * * * *


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     IN WITNESS WHEREOF, the undersigned have executed this Amendment as of the
date first set forth above.



                                     EQUITY OFFICE PROPERTIES TRUST,
                                     a Maryland real estate investment trust, as
                                     Managing General Partner of EOP
                                     Operating Limited Partnership and on
                                     behalf of existing Limited Partners.


                                     By:/s/ STANLEY M. STEVENS
                                        -----------------------------------

                                     Name: Stanley M. Stevens


                                     Title: Executive Vice President and Chief
                                            Legal Counsel



                                     ZELL/MERRILL LYNCH REAL ESTATE
                                     OPPORTUNITY PARTNERS LIMITED
                                     PARTNERSHIP II, General Partner


                                     By: Equity Office Properties Trust, its
                                         managing general partner


                                         By: /s/ STANLEY M. STEVENS
                                             ------------------------------
                                         Name: Stanley M. Stevens

                                         Title: Executive Vice President and
                                                Chief Legal Counsel




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