EXHIBIT 8.1

EXHIBIT 8.1



September 14, 1999


AvalonBay Communities, Inc.
2900 Eisenhower Avenue, Suite 300
Alexandria, Virginia 22314

Ladies and Gentlemen:

This opinion is delivered to you in our capacity as counsel to AvalonBay
Communities, Inc. (the "Company") in connection with the registration on Form
S-3 (the "Registration Statement") pursuant to the Securities Act of 1933, as
amended (the "Securities Act"), which relates to the possible sale from time
to time of up to 267,553 shares (the "Redemption Shares") of common stock,
par value $.01 per share ("Common Stock"), of the Company by holders of units
of limited partnership interest ("Units") in Bay Pacific Northwest, L.P., a
Delaware limited partnership (the "Partnership"), of which the Company is the
sole general partner. The holders of the Units may receive the Redemption
Shares (together with rights to purchase shares of Series E Junior
Participating Cumulative Preferred Stock, par value $.01 per share, which are
attached to all shares of Common Stock) upon the tender of such holder's
Units to the Partnership for redemption and the Company exercises its right
pursuant to the Partnership's Agreement of Limited Partnership, as amended,
to issue the Redemption Shares in exchange for such tendered Units. This
opinion relates to the Company's qualification for federal income tax
purposes as a real estate investment trust (a "REIT") under the Internal
Revenue Code of 1986, as amended (the "Code"), for taxable years commencing
with the Company's taxable year ended December 31, 1994.

We have relied upon the representations of an officer of the Company regarding
the manner in which the Company has been and will continue to be owned and
operated and the continued accuracy of such representations through the date of
this letter. We assume that the Company has been and will be operated in
accordance with applicable laws and the terms and conditions of applicable
documents, and that the descriptions of the Company and its investments, and the
proposed investments, activities, operations and governance of the Company set
forth in the Registration Statement continue to be true. In addition, we have
relied on certain additional facts and assumptions described below.

In rendering the following opinion, we have examined the Company's articles
of incorporation, as amended, the Company's bylaws, as amended, its federal
income tax returns for the taxable years ended December 31, 1994, December
31, 1995, December 31, 1996, and December 31, 1997, on Form 1120-REIT, and
such other records, certificates and documents, each as amended, as we have
deemed necessary or appropriate for purposes of rendering the opinions set
forth herein.

In rendering the opinion set forth herein, we have assumed (i) the
genuineness of all signatures on documents we have examined, (ii) the
authenticity of all documents submitted to us as originals, (iii) the
conformity to the original documents of all documents submitted to us as
copies, (iv) the conformity of final documents to all documents submitted to
us as drafts, (v) the authority and capacity of the individual or individuals
who executed any such documents on behalf of any person, (vi) the accuracy
and completeness of all records made available to us and (vii) the factual
accuracy of all representations, warranties and other statements made by all
parties. We have also assumed, without investigation, that all documents,
certificates, representations, warranties and covenants on which we have
relied in rendering the opinions set forth below and that were given or dated
earlier than the date of this letter continue to remain accurate, insofar as
relevant to the opinions set forth herein, from such earlier date through and
including the date of this letter.

The opinion set forth below is based upon the Code, the Income Tax
Regulations and Procedure and Administration Regulations promulgated
thereunder and existing administrative and judicial interpretations thereof,
all as they exist at the date of this letter. All of the foregoing statutes,
regulations and interpretations




AvalonBay Communities, Inc.
September 14, 1999
Page 2



are subject to change, in some circumstances with retroactive effect; any
changes to the foregoing authorities might result in modifications of our
opinions contained herein. Based upon and subject to the foregoing, and
provided that the Company continues to meet the applicable asset composition,
source of income, shareholder diversification, distribution and other
requirements of the Code necessary for a corporation to qualify as a REIT, we
are of the opinion that commencing with the taxable year ending December 31,
1994, the form of organization of the Company and its operations are such as
to enable the Company to qualify as a "real estate investment trust" under
the applicable provisions of the Code.

We express no opinions other than those expressly set forth herein.
Furthermore, the Company's qualification as a REIT will depend on the Company
meeting, in its actual operations, the applicable asset composition, source
of income, shareholder diversification, distribution, record keeping and
other requirements of the Code necessary for a corporation to qualify as a
REIT. We will not review these operations, and no assurance can be given that
the actual operations of the Company and its affiliates will meet these
requirements or the representations made to us with respect thereto. Our
opinions are not binding on the IRS and the IRS may disagree with the
opinions contained herein. Except as specifically discussed above, the
opinion expressed herein is based upon the law as it currently exists.
Consequently, future changes in the law may cause the federal income tax
treatment of the transactions described herein to be materially and adversely
different from that described above.

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. In giving such consent, we do not thereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act or the rules and regulations of the Securities and Exchange
Commission thereunder.

Very truly yours,

/s/ Goodwin, Procter & Hoar LLP

Goodwin, Procter & Hoar LLP