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                                                                    EXHIBIT 5.1


                           GOODWIN, PROCTER & HOAR LLP

                               COUNSELLORS AT LAW
                                 EXCHANGE PLACE
                        BOSTON, MASSACHUSETTS 02109-2881

                                                      TELEPHONE (617) 570-l000
                                                     TELECOPIER (617) 523-1231


                                February 2, 1999

New Plan Excel Realty Trust, Inc.
New Plan Realty Trust
1120 Avenue of the Americas
New York, New York  10036

Ladies and Gentlemen:

     Re: Guarantee by New Plan Realty Trust of New Plan Excel Realty Trust, Inc.
         Medium Term Notes Due Nine Months or More From Date of Issue

     As special Massachusetts counsel to New Plan Realty Trust (the
"Guarantor"), we render this opinion in connection with the offer and sale by
New Plan Excel Realty Trust, Inc. (the "Company"), the holder of all outstanding
shares of beneficial interest of the Guarantor, of up to U.S. $500,000,000
aggregate initial amount (or its equivalent, based upon the applicable exchange
rate at the time of issuance, in such foreign or composite currencies as the
Company shall designate at the time of issuance) of the Company's Medium Term
Notes Due Nine Months or More from Date of Issue ("Notes"), which are to be
established as a series of senior debt securities of the Company under an
indenture among the Company as Primary Obligor, the Guarantor as Guarantor and
State Street Bank & Trust Company as Trustee (the "Indenture"). We are advised
that the Notes may be offered and sold from time to time by the Company directly
or to or through Agents pursuant to a Distribution Agreement (the "Distribution
Agreement") to which the Company, the Guarantor and the Agents are parties.
Under the Indenture, the Guarantor undertakes to guarantee the payment of
principal, premium if any and interest of and on the Notes (the "Guarantee").

     We have reviewed the Company's Registration Statement No. 333-67511 on
Form S-3 as filed with the Securities and Exchange Commission (the "Registration
Statement"), including the Prospectus Supplement describing the Notes, and
observe that each issue of Notes will be accompanied by a pricing supplement
that will contain the specific description of the Notes being offered and the
terms of the offering (a "Pricing Supplement").

     We have also reviewed (i) copies of the Guarantor's Amended and Restated
Declaration of Trust dated January 15, 1996 as filed with the Secretary of the
Commonwealth of Massachusetts on March 12, 1996 and all subsequent amendments
thereto filed with the Secretary of the 
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New Plan Excel Realty Trust, Inc.
New Plan Realty Trust
February 2, 1999
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Commonwealth of Massachusetts to date (the "Declaration of Trust"); (ii) a
Certificate of recent date of the Secretary of the Commonwealth of Massachusetts
as to filings made by the Guarantor and the authority of the Guarantor to
transact business in Massachusetts; (iii) a Certificate of even date of the
Secretary of the Guarantor reciting the adoption of resolutions pertaining to
the Guarantor's Guarantee of the Notes; (iv) a Certificate of even date of an
officer of the Guarantor as to certain factual matters; (v) copies furnished to
us on your behalf of the following documents in the respective forms represented
to us as to be executed by the parties thereto: (A) the Indenture and (B) the
Distribution Agreement; and (vi) such other documents and certificates as we
deem appropriate for the purposes of this opinion.

       We have made no independent examination as to the truth, accuracy,
completeness or content of the facts contained in any representation, warranty,
covenant or other statement made by or on behalf of either the Company or the
Guarantor in any of the aforesaid documents or in any other document executed or
furnished by the Company or the Guarantor in connection therewith. We have
assumed the accuracy of all such facts as well as the genuineness of all
signatures and the conformity to original documents of all documents submitted
to or examined by us as copies.

       Our opinions herein are limited to matters of the law of the Commonwealth
of Massachusetts, and we express no opinion herein concerning the law of any
other jurisdiction.

       Subject to the foregoing and the other matters set forth herein, it is
our opinion that:

       1.   The Guarantor has been duly established and is validly existing and
in good standing as an unincorporated association commonly referred to as a
business trust pursuant to its Declaration of Trust under the laws of the
Commonwealth of Massachusetts.

       2.   The Indenture has been duly authorized by the Guarantor and, when
the Indenture is executed and delivered by the Guarantor, assuming due
authorization, execution and delivery of the Indenture by each of the Company
and the Trustee, and when Notes are issued, authenticated and delivered pursuant
to the Indenture against payment of the consideration therefor in accordance
with the terms of the applicable Pricing Supplement, the obligations of the
Guarantor under the Indenture, including its Guarantee of the Notes that
constitute Debt Guarantees under the Registration Statement, will constitute
valid and binding obligations of the Guarantor.
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New Plan Excel Realty Trust, Inc.
New Plan Realty Trust
February 2, 1999
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       We consent to a copy of this opinion being filed as an exhibit to the
Registration Statement (whether pursuant to a post-effective amendment thereto
or as an exhibit to a Form 8-K report to be filed by the Company).


                                Very truly yours,

                                /s/ Goodwin, Procter & Hoar LLP
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                                Goodwin, Procter & Hoar LLP