As filed with the Securities and Exchange Commission on April 11, 2005
                                                     REGISTRATION NO. 333-______
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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                             ----------------------

                                    FORM S-8
                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

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                               ACUITY BRANDS, INC.
             (Exact name of registrant as specified in its charter)

            DELAWARE                                         58-2632672
 (State or other jurisdiction of                          (I.R.S. Employer
 incorporation or organization)                          Identification No.)

                               ACUITY BRANDS, INC.
                           1170 PEACHTREE STREET, N.E.
                                   SUITE 2400
                             ATLANTA, GEORGIA 30309
                                 (404) 853-1400
   (Address, including zip code, of registrant's principal executive offices)

                         ACUITY BRANDS, INC. 401(k) PLAN
                         -------------------------------

                              (Full title of plans)

                                KENYON W. MURPHY
                    SENIOR VICE PRESIDENT AND GENERAL COUNSEL
                               ACUITY BRANDS, INC.
                           1170 PEACHTREE STREET, N.E.
                                   SUITE 2400
                             ATLANTA, GEORGIA 30309
                                 (404) 853-1400

                (Name, address, including zip code, and telephone
               number, including area code, of agent for service)

                         CALCULATION OF REGISTRATION FEE



                                                               Proposed Maximum  Proposed Maximum
                                                 Amount to      Offering Price       Aggregate          Amount of
Title of Securities to be Registered           be Registered     Per Share(1)    Offering Price(1)  Registration Fee
                                                                                        
Common Stock,
par value $0.01 per share....................   423,768 shares       $26.85          $11,378,171             $1,340

Preferred Stock Purchase Rights..............       (2)                N/A                 N/A              N/A

Interests in the 401(k) Plan.................       (3)                N/A                 N/A              N/A


(1)   Estimated solely for the purpose of computing the registration fee
      pursuant to Rule 457(h) on the basis of the average of the high and low
      sales prices per share ($26.85 per share) of Common Stock of Acuity
      Brands, Inc. as reported on the New York Stock Exchange on April 5, 2005.

(2)   This Registration Statement also covers the associated Preferred Stock
      Purchase Rights (the "Rights") issued pursuant to the Stockholder
      Protection Rights Agreement, dated as of November 12, 2001, between Acuity
      Brands, Inc. and Wells Fargo Bank Minnesota, N.A. (as modified from time
      to time). Until the occurrence of certain events, the Rights will not be
      exercisable for or evidenced separately from shares of common stock, par
      value $0.01 per share, of Acuity Brands, Inc.

(3)   Pursuant to Rule 416(c) of the Securities Act of 1933, this Registration
      Statement also covers an indeterminate amount of interests to be offered
      or sold pursuant to the Acuity Brands, Inc. 401(k) Plan.

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                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

      Effective January 1, 2003, Acuity Brands, Inc. ("Acuity," the "Registrant"
or the "Company") merged the Acuity Brands, Inc. 401(k) Plan for Corporate
Employees, as amended (the "Corporate Plan"), with and into the Acuity Lighting
Group, Inc. Profit Sharing and Retirement Plan for Salaried Employees, as
amended (the "ALG Plan"). At such time, the name of the combined plan was
changed to the Acuity Brands, Inc. 401(k) Plan (the "401(k) Plan"). This
Registration Statement and the accompanying prospectus relate to an aggregate of
423,768 shares of the Registrant's common stock, par value $0.01 per share (the
"Common Stock") reserved for issuance under the 401(k) Plan.

      The document(s) containing the information specified in Part I of Form S-8
will be sent or given to employees of the Registrant as specified by Rule
428(b)(1) of the Securities Act of 1933, as amended (the "Securities Act"). In
accordance with the instructions of Part I of Form S-8, such documents will not
be filed with the Securities Exchange Commission (the "Commission") either as
part of this Registration Statement or as prospectuses or prospectus supplements
pursuant to Rule 424 of the Securities Act. These documents and the documents
incorporated by reference in this Registration Statement pursuant to Item 3 of
Part II of this Registration Statement, taken together, constitute a prospectus
that meets the requirements of Section 10(a) of the Securities Act.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference.

      The following documents have been previously filed by the Registrant with
the Commission and are hereby incorporated by reference into this Registration
Statement as of their respective dates:

         (a)   Annual Report on Form 10-K for the year ended August 31, 2004;

         (b)   Quarterly Reports on Form 10-Q for the quarters ended November
               30, 2004 and February 28, 2005;

         (c)   Current Reports on Form 8-K, filed with the Commission on
               September 2, 2004, October 5, 2004, January 12, 2005, February
               22, 2005 and April 1, 2005; and

         (d)   the description of the Common Stock contained in the Registrant's
               Registration Statement on Form 10, as originally filed with the
               Securities and Exchange Commission on July 3, 2001, as amended,
               including any amendment or report filed for the purpose of
               updating such description.

      In addition, all documents filed by the Registrant pursuant to Sections
13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act") subsequent to the date of this Registration Statement and
prior to the filing of a post-effective amendment to this Registration Statement
that indicates that all securities offered hereunder have been sold or that
deregisters all such securities then remaining unsold shall be deemed to be
incorporated by reference into this Registration Statement and to be a part
hereof from the date of the filing of such documents.

      Any statement contained in any document incorporated or deemed to be
incorporated by reference into this Registration Statement shall be deemed to be
modified or superseded for purposes thereof to the extent that a statement
contained therein or in any other subsequently filed document that is also
incorporated or deemed to be incorporated therein by reference modifies or
supersedes such statement. Any such statement so modified or superseded shall
not be deemed to constitute a part of this Registration Statement.



Item 4.  Description of Securities.

         Inapplicable.

Item 5.  Interest of Named Experts and Counsel.

         Inapplicable.

Item 6.  Indemnification of Directors and Officers.

      Acuity's By-laws and Section 145 of the Delaware General Corporation Law,
which allows, and in some cases requires, the indemnification of directors and
officers under certain circumstances, grant Acuity's directors and officers a
right to indemnification to the fullest extent permitted by law for all expenses
relating to civil, criminal, administrative or investigative procedures to which
they are a party (i) by reason of the fact that they are or were directors or
officers of Acuity or (ii) by reason of the fact that, while they are or were
directors or officers of Acuity, they are or were serving at the request of
Acuity as a director, officer or employee of another enterprise. Acuity's
By-laws further provide that an advancement for any such expenses shall only be
made upon delivery to Acuity by the indemnitee of an undertaking to repay all
amounts so advanced if it is ultimately determined that such indemnitee is not
entitled to be indemnified by Acuity.

      Acuity has also entered into indemnification agreements with certain of
its directors and officers. These agreements require Acuity to indemnify these
directors and officers with respect to their activities as directors or officers
of Acuity or when serving at Acuity's request as a director, officer or trustee
of another corporation, trust or other enterprise against expenses (including
attorneys' fees, judgments, fines and amounts paid in settlement) actually and
reasonably incurred by them in any threatened, pending or completed suit or
proceeding (civil, criminal, administrative or investigative) to which they are,
or are threatened to be made, parties as a result of their service to Acuity.
Acuity has agreed to indemnify each indemnitee for any one or a combination of
the following, whichever is most advantageous to the indemnitee, as determined
by the indemnitee (i) the benefits provided by Acuity's certificate of
incorporation and By-laws in effect on the date of the indemnification
agreement; (ii) the benefits provided by Acuity's certificate of incorporation
and By-laws at the time expenses are incurred by the indemnitee; (iii) the
benefits allowable under Delaware law in effect on the date of the
indemnification agreement; (iv) the benefits allowable under the law of the
jurisdiction under which Acuity exists at the time expenses are incurred by the
indemnitee; (v) the benefits available under liability insurance obtained by
Acuity; and (vi) such other benefits as may be otherwise available to indemnitee
under Acuity's existing practices. Under the indemnification agreements, each
indemnitee will continue to be indemnified even after ceasing to occupy a
position as an officer, director, employee or agent of Acuity with respect to
suits or proceedings arising out of acts or omissions during his service to
Acuity. Each indemnitee has agreed to notify Acuity promptly of any proceeding
brought or threatened and not to make any admission or settlement without
Acuity's consent, unless the indemnitee determines to undertake his own defense
and waives the benefits of the indemnification agreement.

Item 7.  Exemption from Registration Claimed.

         Inapplicable.





Item 8.  Exhibits.



Exhibit                                                      Description
-------                                                      -----------
         

4.1         Restated Certificate of Incorporation of the Registrant, filed as Exhibit 3.1 to the Registrant's Current Report on Form
            8-K as filed with the Commission on December 14, 2001 and incorporated herein by reference.

4.2         Amended and Restated Bylaws of the Registrant, filed as Exhibit 3(b) to the Registrant's Quarterly Report on Form 10-Q
            for the quarter ended May 31, 2004 and incorporated herein by reference.

4.3         Form of Common Stock certificate, filed as Exhibit 4.1 to Amendment No. 5 to the Registrant's Registration Statement on
            Form 10, filed with the Commission on November 9, 2004 and incorporated herein by reference.

4.4         Stockholder Protection Rights Agreement, dated as of November 12, 2001, between the Registrant and Wells Fargo Bank
            Minnesota, N.A., filed as Exhibit 4.2 to the Registrant's Current Report on Form 8-K as filed with the Commission on
            December 14, 2001 and incorporated herein by reference.

4.5         Letter Agreement appointing Successor Rights Agent, dated June 5, 2003, filed as Exhibit 4(c) to the Registrant's
            Quarterly Report on Form 10-Q for the quarter ended May 31, 2003 and incorporated herein by reference.

5.1*        Opinion of Kenyon W. Murphy, Esq. regarding legality of shares being registered.

23.1*       Consent of Ernst & Young LLP

23.2*       Consent of Kenyon W. Murphy, Esq. (included in Exhibit 5.1)

24.1*       Powers of Attorney


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*     Filed herewith

Item 9.  Undertakings.

      The undersigned Registrant hereby undertakes:

      (a) (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this Registration Statement;

         (i)   To include any prospectus required by Section 10(a)(3) of the
               Securities Act;

         (ii)  To reflect in the prospectus any facts or events arising after
               the effective date of this Registration Statement (or the most
               recent post-effective amendment thereof) which, individually or
               in the aggregate, represent a fundamental change in the
               information set forth in this Registration Statement;

         (iii) To include any material information with respect to the plan of
               distribution not previously disclosed in this Registration
               Statement or any material change to such information in this
               Registration Statement;



      provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply
      if the information required to be included in a post-effective amendment
      by those paragraphs is contained in periodic reports filed with or
      furnished to the Commission by the Registrant pursuant to Section 13 or
      15(d) of the Exchange Act that are incorporated by reference in this
      Registration Statement.

            (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

      (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
Registrant's annual report pursuant to Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 (and, where applicable, each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities Exchange Act)
of 1934 that is incorporated by reference in the Registration Statement shall be
deemed to be a new registration statement relating to the securities offered
therein, and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.

      (c) Insofar as indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons
of the Registrant pursuant to the foregoing provisions, or otherwise, the
Registrant has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                     EXPERTS

      The consolidated financial statements of Acuity Brands, Inc. appearing in
Acuity Brands, Inc.'s Annual Report on Form 10-K for the fiscal year ended
August 31, 2004 (including the schedules appearing therein) have been audited by
Ernst & Young LLP, independent registered public accounting firm, as set forth
in their report thereon included therein and incorporated herein by reference.
Such consolidated financial statements are incorporated herein by reference in
reliance upon such report given on the authority of such firm as experts in
accounting and auditing.



                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, Acuity Brands,
Inc. has duly caused this Registration Statement to be signed on its behalf by
the undersigned, thereunto duly authorized, in the City of Atlanta, State of
Georgia, on this 11th day of April, 2005.

                                         ACUITY BRANDS, INC.

                                         By: /s/ Vernon J. Nagel
                                            ------------------------------------
                                            Vernon J. Nagel
                                            Chairman and Chief Executive Officer

      KNOW ALL MEN BY THESE PRESENTS, pursuant to the requirements of the
Securities Act of 1933, this Registration Statement has been signed by the
following persons in the capacities indicated on April 11, 2005.



Signature                                                            Title
---------                                                            -----
                                      
      *                                  Chairman and Chief Executive Officer
--------------------------
Vernon J. Nagel

      *                                  Vice President, Controller, and Interim Chief Financial Officer
--------------------------
Karen J. Holcom

      *                                  Director
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Peter C. Browning

      *                                  Director
--------------------------
John L. Clendenin

      *                                  Director
--------------------------
Jay M. Davis

      *                                  Director
--------------------------
Earnest W. Deavenport, Jr.

      *                                  Director
--------------------------
Robert F. McCullough

      *                                  Director
--------------------------
Julia B. North

      *                                  Director
--------------------------
Ray M. Robinson

      *                                  Director
--------------------------
Neil Williams


* By: /s/ Kenyon W. Murphy
      -------------------------------------------
        Kenyon W. Murphy
        Attorney-in-Fact