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                                                                     EXHIBIT 4.2


                        ARDEN REALTY LIMITED PARTNERSHIP

                           8.50% Senior Note due 2010


No. 001                                                            $100,000,000
CUSIP No. 03979GAH8

UNLESS THIS NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY
TRUST COMPANY, A NEW YORK CORPORATION ("DTC") (55 WATER STREET, NEW YORK, NEW
YORK) TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR
PAYMENT, AND SUCH NOTE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO., OR SUCH
OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC, AND ANY PAYMENT
IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC, ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

UNLESS AND UNTIL THIS NOTE IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN
CERTIFICATED FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY DTC TO
A NOMINEE THEREOF OR BY A NOMINEE THEREOF TO DTC OR ANOTHER NOMINEE OF DTC OR BY
DTC OR ANY SUCH NOMINEE TO A SUCCESSOR OF DTC OR A NOMINEE OF SUCH SUCCESSOR.

THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO BE BOUND BY THE
PROVISIONS OF THE REGISTRATION RIGHTS AGREEMENT DATED AS OF NOVEMBER 20, 2000,
BETWEEN ARDEN REALTY LIMITED PARTNERSHIP AND THE INITIAL PURCHASER RELATING TO
THE NOTE.

     ARDEN REALTY LIMITED PARTNERSHIP, a Maryland limited partnership (herein
referred to as the "Issuer," which term includes any successor issuer under the
Indenture hereinafter referred to), for value received, hereby promises to pay
to Cede & Co., or registered assigns, the principal sum of One Hundred Million
Dollars on November 15, 2010 (the "Stated Maturity Date") or the date fixed for
earlier redemption (the "Redemption Date," and together with the Stated Maturity
Date with respect to principal repayable on such date, the "Maturity Date"), and
to pay interest thereon from November 20, 2000, or from the most recent Interest
Payment Date to which interest has been paid or duly provided for, semi-annually
in arrears on November 15 and May 15 of each year (each, an "Interest Payment
Date"), commencing May 15, 2001, and on the Maturity Date at the rate of 8.50%
per annum, until the principal hereof is paid or duly provided for.

     The interest so payable, and punctually paid or duly provided for, on any
Interest Payment Date and on the Maturity Date will, as provided in such
Indenture, be paid to the



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Holder in whose name this Note (or one or more Predecessor Securities) is
registered at the close of business on the Regular Record Date for such payment,
which shall be the date 15 calendar days (regardless of whether such day is a
Business Day), next preceding such Interest Payment Date or the Maturity Date at
the office or agency of the Issuer maintained for such purpose. Any such
interest not so punctually paid or duly provided for shall forthwith cease to be
payable to the Holder on such Regular Record Date, and may be paid to the Holder
in whose name this Note (or one or more Predecessor Securities) is registered at
the close of business on a Special Record Date for the payment of such Defaulted
Interest to be fixed by the Trustee hereinafter referred to, notice whereof
shall be given to Holders of Notes of this series not less than 10 days prior to
such Special Record Date, or may be paid at any time in any other lawful manner
not inconsistent with the requirements of any securities exchange on which the
Notes of this series may be listed, and upon such notice as may be required by
such exchange, all as more fully provided in the Indenture. Interest on this
Note will be computed on the basis of a 360-day year of twelve 30-day months.

     The principal of this Note payable on the Maturity Date will be paid
against presentation and surrender of this Note at the Corporate Trust Office of
the Trustee maintained for that purpose in the Borough of Manhattan, the City of
New York, in such coin or currency of the United States of America as at the
time of payment is legal tender for the payment of public and private debts.

     Interest payable on this Note on any Interest Payment Date and on the
Maturity Date, as the case may be, will be the amount of interest accrued during
the applicable Interest Period (as defined below).

     An "Interest Period" is each period from and including the immediately
preceding Interest Payment Date in respect of which interest has been paid or
duly provided for (or from and including November 20, 2000, if no interest has
been paid on this Note) to but excluding such Interest Payment Date or the
Maturity Date, as the case may be. If any Interest Payment Date or Maturity Date
falls on a day that is not a Business Day, as defined below, principal and
interest payable with respect to such Interest Payment Date or Maturity Date, as
the case may be, will be paid on the next succeeding Business Day with the same
force and effect as if it were paid on the date such payment was due, and no
interest shall accrue on the amount so payable for the period from and after
such Interest Payment Date or Maturity Date, as the case may be. "Business Day"
means any day, other than a Saturday or Sunday that is neither a legal holiday
nor a day on which banking institutions in the City of New York are authorized
or required by law, regulation or executive order to close.

     Payments of principal and interest in respect of this Note will be made by
U.S. dollar check or by wire transfer (such a wire transfer to be made only to a
Holder of an aggregate principal amount of Securities in excess of $5,000,000,
and only if such Holder shall have furnished wire instructions in writing to the
Trustee no later than 15 days prior to the relevant payment date and
acknowledged that a wire transfer fee shall be payable) of immediately available
funds in such coin or currency of the United States of America as at the time of
payment is legal tender for the payment of public and private debts.



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     The Holder of this Security is entitled to the benefits of and is subject
to the obligations contained in a Registration Rights Agreement (subject to the
provisions thereof), dated as of November 20, 2000, between the Issuer and the
Initial Purchaser (the "Registration Rights Agreement").

     This Note is one of a duly authorized issue of debentures, notes, bonds or
other evidences of indebtedness of the Issuer (herein called the "Securities")
of the series hereafter specified, all issued or to be issued under an
Indenture, dated as of March 14, 2000 (herein called the "Indenture"), duly
executed and delivered by the Issuer to The Bank of New York, as Trustee (herein
called the "Trustee," which term includes any successor trustee under the
Indenture with respect to the series of Securities of which this Note is a
part), to which Indenture and all indentures supplemental thereto reference is
hereby made for a statement of the rights, limitations of rights, obligations,
duties and immunities thereunder of the Issuer, the Trustee and the Holders of
the Securities, and of the terms upon which the Securities are, and are to be,
authenticated and delivered. The Securities may be issued in one or more series,
which different series may be issued in various aggregate principal amounts, may
mature at different times, may bear interest (if any) at different rates, may be
subject to different redemption provisions (if any), and may otherwise vary as
provided in the Indenture. This Note is one of a series of Securities designated
as the 8.50% Senior Notes due 2010 (the "Notes"), and the aggregate principal
amount of the Notes to be issued under such series is unlimited.

     In case an Event of Default with respect to the Notes shall have occurred
and be continuing, the principal hereof and the Make-Whole Amount (if any) may
be declared, and upon such declaration shall become, due and payable, in the
manner, with the effect, and subject to the conditions provided in the
Indenture.

     The Issuer may redeem the Securities at any time, in whole or in part, at
the election of the Issuer, at a redemption price equal to the sum of (1) the
principal amount of the Securities being redeemed plus accrued interest thereon
to the Redemption Date, and (2) the Make-Whole Amount, if any, with respect to
such Securities (the "Redemption Price"). Notice of optional redemption of any
Securities will be given to Holders at their addresses, as shown in the security
register for the Notes, not less than 30 nor more than 60 days prior to the
Redemption Date. The notice of redemption will specify, among other items, the
Redemption Price and the principal amount of the Securities held by such Holder
to be redeemed. If less than all the Notes are to be redeemed at the option of
the Issuer, the Issuer will notify the Trustee at least 45 days prior to giving
notice of redemption to the Holders (or such shorter period as is satisfactory
to the Trustee) of the aggregate principal amount of Notes to be redeemed and
their redemption date. The Trustee shall select, in such manner as it shall deem
fair and appropriate, Notes to be redeemed in whole or in part.

     Subject to certain limitations in the Indenture, at any time when the
Issuer is not subject to Section 13 or 15(d) of the United States Securities
Exchange Act of 1934, as amended, upon the request of a Holder of a Restricted
Security (as defined in the Registration Rights Agreement) the Issuer will
promptly furnish or cause to be furnished Rule 144A Information (as defined in
the Registration Rights Agreement) to such Holder of Restricted Securities, or
to a prospective purchaser of any security designated by any such Holder to the
extent required to


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permit compliance by such Holder with Rule 144A under the Securities Act in
connection with the resale of any such security.

     In the event of redemption of this Note in part only, a new Note or Notes
for the unredeemed portion hereof shall be issued in the name of the Holder
hereof upon the cancellation hereof.

     The Indenture contains provisions permitting the Issuer and the Trustee,
with the consent of the Holders of not less than a majority of the aggregate
principal amount of the Securities at the time Outstanding of each series to be
affected, evidenced as provided in the Indenture, to execute supplemental
Indentures adding any provisions to or changing in any manner or eliminating any
of the provisions of the Indenture or of any supplemental Indenture or modifying
in any manner the rights of the Holders of the Securities of each series;
provided, however, that no such supplemental Indenture shall, without the
consent of the Holder of each Security so affected, (i) change the final
maturity of any Security, or reduce the principal amount thereof or any premium
thereon, or reduce the rate or extend the time of payment of any interest
thereon, or impair or affect the rights of any Holder to institute suit for the
payment on any Security, or (ii) reduce the aforesaid percentage of Securities,
the Holders of which are required to consent to any such supplemental Indenture,
or (iii) reduce the percentage of Securities, the Holders of which are required
to consent to any waiver of compliance with certain provisions of the Indenture
or any waiver of certain defaults thereunder. It is also provided in the
Indenture that, with respect to certain defaults or Events of Default regarding
the Securities of any series, the Holders of a majority in aggregate principal
amount outstanding of the Securities of such series (or, in the case of certain
defaults or Events of Default, all series of Securities) may on behalf of the
Holders of all the Securities of such series (or all of the Securities, as the
case may be) waive any such past default or Event of Default and its
consequences, prior to any declaration accelerating the maturity of such
Securities, or, subject to certain conditions, may rescind a declaration of
acceleration and its consequences with respect to such Securities. The preceding
sentence shall not, however, apply to a default in the payment of the principal
of or premium, if any, or interest on any of the Securities. Any such consent or
waiver by the Holder of this Security (unless revoked as provided in the
Indenture) shall be conclusive and binding upon such Holder and upon all future
Holders and owners of this Security and any securities that may be issued in
exchange or substitution hereof, irrespective of whether or not any notation
thereof is made upon this Security or such other securities.

     No reference herein to the Indenture and no provision of this Note or of
the Indenture shall alter or impair the obligation of the Issuer, which is
absolute and unconditional, to pay the principal of and any Make-Whole Amount
and interest on this Note in the manner, at the respective times, places and
rate, and in the coin or currency, herein prescribed.

     As provided in and subject to the provisions of the Indenture, the Holder
of this Security shall not have the right to institute any proceeding with
respect to the Indenture or for the appointment of a receiver or trustee or for
any other remedy thereunder unless (a) such Holder shall have previously given
the Trustee written notice of a continuing Event of Default, (b) the Holders of
not less than 25% in aggregate principal amount of the Securities Outstanding
shall have made written request to the Trustee to institute proceedings in
respect of such Event of Default as Trustee and offered the Trustee reasonable
indemnity and the Trustee shall not have



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received from the Holders of a majority in aggregate principal amount of the
Securities Outstanding a direction inconsistent with such request, and (c) the
Trustee shall have failed to institute any such proceeding, for 60 days after
receipt of such notice, request and offer of indemnity. The foregoing shall not
apply to any suit instituted by the Holder of this Security for the enforcement
of any payment of principal hereof, Make-Whole Amount, if any, or interest
hereon on or after the respective due dates expressed herein.

     This Security is not subject to a sinking fund requirement.

     The Indenture contains provisions for defeasance at any time of (i) the
entire indebtedness of this Security (ii) certain restrictive covenants with
respect to this Security, in each case upon compliance with certain conditions
set forth therein.

     No recourse under or upon any obligation, covenant or agreement contained
in the Indenture, in any Security or coupon appertaining thereto, or because of
any indebtedness evidenced hereby or thereby (including, without limitation, any
obligation or indebtedness relating to the principal of, or premium or
Make-Whole Amount, if any, interest or any other amounts due, or claimed to be
due, on this Security), or for any claim based thereon or otherwise in respect
thereof, shall be had (i) against the General Partner or any other partner, or
any Person which owns an interest, directly or indirectly, in any partner, in
the Issuer, or (ii) against any promoter, as such, or against any past, present
or future shareholder, officer, trustee or partner, as such, of the Issuer or
the General Partner or of any successor, either directly or through the Issuer
or the General Partner or any successor, under any rule of law, statute or
constitutional provision or by the enforcement of any assessment or by any legal
or equitable proceeding or otherwise, all such liability being expressly waived
and released by the acceptance hereof and as part of the consideration for the
issue hereof.

     The Securities of this series are issuable only in registered form without
coupons in denominations of $1,000 and any integral multiple thereof. As
provided in the Indenture and subject to certain limitations therein and herein
set forth, this Note is exchangeable for a like aggregate principal amount of
Notes of different authorized denominations but otherwise having the same terms
and conditions, as requested by the Holder hereof surrendering the same. No
service charge shall be made for any such registration of transfer or exchange,
but the Issuer may require payment of a sum sufficient to cover any tax or other
governmental charge payable in connection therewith.

     Prior to due presentment of this Note for registration of transfer, the
Issuer, the Trustee and any agent of the Issuer or the Trustee may deem and
treat the Person in whose name this Security is registered as the absolute owner
of this Security (whether or not this Security shall be overdue and
notwithstanding any notation of ownership or other writing hereon), for the
purpose of receiving payment of, or on account of, the principal hereof and
Make-Whole Amount, if any, and subject to the provisions herein and on the face
hereof; interest hereon and for all other purposes, and neither the Issuer, the
Trustee nor any such agent shall be affected by notice to the contrary.

     THE INDENTURE AND THIS SECURITY SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.


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     Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures, the Issuer has caused CUSIP numbers to be
printed on the Notes as a convenience to the Holders of the Notes. No
representation is made as to the correctness or accuracy of such CUSIP numbers
as printed on the Notes, and reliance may be placed only on the other
identification numbers printed hereon.

     Capitalized terms used herein and not defined herein shall have the
respective meanings given to such terms in the Indenture.

     Unless the Certificate of Authentication hereon has been executed by the
Trustee by one of its authorized signatories, this Note shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.



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     IN WITNESS WHEREOF, the Issuer has caused this instrument to be signed
manually or by facsimile by its duly authorized officers.

Dated:               , 2001



                               ARDEN REALTY LIMITED PARTNERSHIP



                               By: Arden Realty, Inc., its sole general partner

                               By:
                                  ----------------------------------------------
                                  Richard S. Davis
                                  Senior Vice President, Co-Chief Financial
                                  Officer and Treasurer




Attest:


-----------------------------
David A. Swartz
General Counsel and Secretary


TRUSTEE'S CERTIFICATE OF AUTHENTICATION

This is one of the Notes of the series designated herein referred to in the
within-mentioned Indenture.



                               THE BANK OF NEW YORK
                                      as Trustee


                               By:
                                  ---------------------------------------------
                                             Authorized Signatory



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                         FORM OF TRANSFEREE CERTIFICATE


     I or we assign and transfer this Security to:





     Please insert social security or other identifying number of assignee

     Print or type name, address and zip code of assignee and irrevocably
appoint ______________________________________ as Agent, to transfer this
Security on the books of the Company. The Agent may substitute another to act
for him.



     Dated                      Signed
          ---------------------        ----------------------------------
           (Sign exactly as name appears on the other side of this Security)



     [Signature must be guaranteed by an eligible Guarantor Institution (banks,
stock brokers, savings and loan association and credit unions) with membership
in an approved guarantee medallion program pursuant to Securities and Exchange
Commission Rule 17 Ad-15]