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                                                                    EXHIBIT 5.1

                      [Letterhead of Goodwin Procter LLP]

                               September 17, 2003

Gables Residential Trust
Gables Realty Limited Partnership
777 Yamato Road, Suite 510
Boca Raton, FL 33431

      Re:  Legality of Securities to be Registered
           Under Registration Statement On Form S-3

Ladies and Gentlemen:

         This opinion is delivered in our capacity as counsel to Gables
Residential Trust, a Maryland real estate investment trust (the "Company") and
Gables Realty Limited Partnership, a Delaware limited partnership (the
"Operating Partnership"), in connection with a joint registration statement on
Form S-3 (the "Registration Statement") filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, which relates to the
sale from time to time of an indeterminate amount of (i) preferred shares, par
value $.01 per share ("Preferred Shares"), common shares, par value $.01 per
share ("Common Shares"), depositary shares representing interests in Preferred
Shares ("Depositary Shares") and warrants ("Warrants") to purchase Preferred
Shares or Common Shares, or any combination of Preferred Shares, Common Shares,
Depositary Shares or Warrants (collectively, the "Equity Securities"), of the
Company having a maximum aggregate public offering price of $500,000,000 and
(ii) debt securities ("Debt Securities") of the Operating Partnership having a
maximum aggregate public offering price of $500,000,000 (collectively, the
"Securities"). The Registration Statement provides that the Securities may be
offered separately or together, in separate series, in amounts, at prices and on
terms to be set forth in one or more prospectus supplements (each a "Prospectus
Supplement") to the prospectus contained in the Registration Statement.

         In connection with this opinion, we have examined the amended and
restated declaration of trust of the Company, as amended to the date hereof and
on file with the Maryland State Department of Assessments and Taxation, the
second amended and restated bylaws of the Company, as amended, the seventh
amended and restated agreement of limited partnership of the Operating
Partnership, as amended, such records of corporate and partnership proceedings
of the Company and the Operating Partnership, respectively, as we have deemed
appropriate for the purposes of this opinion, the Registration Statement and the
exhibits thereto.
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Gables Residential Trust
Gables Realty Limited Partnership
September 17, 2003
Page 2

         In rendering the opinions expressed below, we have assumed and have not
verified the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, the conformity to original documents of all
documents submitted to us as certified or photostatic copies, the authenticity
of the originals of such latter documents, and the legal capacity of each
individual executing any document.

         We express no opinion concerning the laws of any jurisdictions other
than the laws of the United States of America, The Commonwealth of
Massachusetts, the State of New York, the Maryland General Corporation Law and
the Delaware Revised Uniform Limited Partnership Act.

         Based upon the foregoing, we are of the opinion that:

           (1)   when the Equity Securities are specifically authorized for
issuance by the Company's Board of Trustees or an authorized committee thereof
(the "Authorizing Resolution"), (ii) upon receipt by the Company of the full
consideration therefor as provided in the Authorizing Resolution and (iii) upon
the issuance of the Equity Securities as described in the Registration Statement
and a Prospectus Supplement that is consistent with the Authorizing Resolution,
the Equity Securities will be legally issued, fully paid and nonassessable and
the and Warrants will be binding obligations of the Company; and

           (2)   when the Debt Securities are specifically authorized for
issuance by the General Partner of the Operating Partnership (the "General
Partner Authorization"), (ii) upon receipt by the Operating Partnership of the
full consideration therefor as provided in the General Partner Authorization and
(iii) upon execution and authentication of the Debt Securities as provided in
the relevant indentures and the issuance of the Debt Securities as described in
the Registration Statement and a Prospectus Supplement that is consistent with
the General Partner Authorization, the Debt Securities will be binding
obligations of the Operating Partnership, enforceable in accordance with their
terms, except that (A) enforcement or the rights and remedies created thereby
may be limited by bankruptcy, insolvency, fraudulent conveyance, reorganization,
moratorium and similar laws of general applicability relating to or affecting
creditors' rights and by equitable principles which may limit the right to
obtain the remedy of specific performance or other injunctive relief and (B) we
express no opinion as the legality, validity or binding nature of an choice of
law provision.

         This opinion shall be interpreted in accordance with the Legal Opinion
Principles issued by the Committee on Legal Opinions of the American Bar
Association's Business Law Section as published in 53 Business Lawyer 831 (May
1998).

         The foregoing assumes that all requisite steps will be taken to comply
with the requirements of the Securities Act and applicable requirements of state
laws regulating the offer and sale of securities.
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Gables Residential Trust
Gables Realty Limited Partnership
September 17, 2003
Page 3

         We hereby consent to being named as counsel to the Company and the
Operating Partnership in the Registration Statement, to the references therein
to our firm under the caption "Legal Matters" and to the inclusion of this
opinion as an exhibit to the Registration Statement.

                                                       Very truly yours,

                                                       /s/ GOODWIN PROCTER  LLP
                                                       ------------------------
                                                           GOODWIN PROCTER  LLP