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                                                                     Exhibit 4.3

                                    GUARANTEE

     CarrAmerica Realty, L.P., a Delaware limited partnership (herein referred
to as the "Guarantor," which term includes any successor Guarantor under the
Indenture dated as of January 11, 2002 (the "Indenture") between CarrAmerica
Realty Corporation (the "Company"), the Guarantor and U.S. Bank National
Association, as the trustee (the "Trustee"), referred to in the Note upon which
this notation is endorsed), (i) has unconditionally guaranteed that (a) the
principal of, interest and premium, if any, on the 5.261% Senior Notes due 2007
(the "Notes") will be promptly paid in full when due, subject to any applicable
grace period, whether at stated maturity, by acceleration or otherwise and
interest on the overdue principal of, and interest on interest, to the extent
lawful, and premium, if any, on the Notes and all other obligations of the
Company to the Holders (as defined in the Indenture) or the Trustee under the
Indenture or the Notes will be promptly paid in full, all in accordance with the
terms set forth in the Indenture and Notes; and (b) in case of any extension of
time of payment or renewal of the Notes or of any such other obligations, the
same will be promptly paid in full when due in accordance with the terms of the
extension or renewal, subject to any applicable grace period, whether at stated
maturity, by acceleration or otherwise, (ii) has agreed to pay any and all costs
and expenses (including reasonable attorneys' fees) incurred by the Trustee or
any Holder in enforcing any rights under this guarantee; provided, however, that
this guarantee is limited as to the Guarantor to the extent necessary not to
constitute a fraudulent conveyance or fraudulent transfer.

     No stockholder, officer, director, or incorporator, as such, past, present
or future, of any Guarantor shall have any personal liability under this
guarantee by reason of his or its status as such stockholder, officer, director
or incorporator.

     This guarantee shall be binding upon the undersigned and, to the extent
provided in the Indenture, its successors and assigns and shall inure to the
benefit of the successors and assigns of the Trustee and the Holders and, in the
event of any transfer or assignment of rights by any Holder or the Trustee, the
rights and privileges herein conferred upon that party shall automatically
extend to and be vested in such transferee or assignee, all subject to the terms
and conditions hereof.

     This guarantee shall not be valid or obligatory for any purpose until the
certificate of authentication on the Note upon which this guarantee is noted
shall have been executed by the Trustee under the Indenture by the manual
signature of one of its authorized officers.

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     IN WITNESS WHEREOF, the Guarantor has caused this guarantee to be duly
executed by its authorized officer.

Dated: November 20, 2002

                                      CARRAMERICA REALTY, L.P.

                                      By:  CarrAmerica Realty GP Holdings, Inc.,
                                           as its general partner


                                           By:   /s/ Thomas A. Carr
                                              ---------------------------------
                                               Name:  Thomas A. Carr
                                               Title: Chief Executive Officer