Exhibit 10.1

AGREEMENT AND PLAN OF MERGER

THIS AGREEMENT AND PLAN OF MERGER (this “Agreement”) is entered into on this
25th day of September, 2007, by and among Acuity Brands, Inc., a Delaware
corporation (the “Company”), Acuity Brands Holdings, Inc., a Delaware
corporation and wholly owned subsidiary of the Company (“Holdings”), and Acuity
Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Holdings
(“Merger Sub”).

WHEREAS, the Company’s authorized capital stock consists of (a) 500,000,000
shares of common stock, par value $0.01 per share (“Company Common Stock”), of
which 43,646,880 shares were issued and outstanding as of July 6, 2007, and
(b) 50,000,000 shares of preferred stock, par value $0.01, of which 5,000,000
shares have been designated as “Participating Preferred Stock” and none of which
is outstanding;

WHEREAS, Holdings’ authorized capital stock consists of (a) 500,000,000 shares
of common stock, par value $0.01 per share (“Holdings Common Stock”), of which
100 shares are currently issued and outstanding and owned by the Company, and
(b) 50,000,000 shares of preferred stock, par value $0.01, of which 5,000,000
shares have been designated as “Participating Preferred Stock” and none of which
is outstanding;

WHEREAS, the designations, rights, and preferences, and the qualifications,
limitations and restrictions of the Holdings Common Stock are the same as those
of the Company Common Stock;

WHEREAS, the Company desires to create a new holding company structure in
accordance with Section 251(g) of the Delaware General Corporation Law (the
“DGCL”) by merging Merger Sub with and into the Company, all in accordance with
the terms of this Agreement;

WHEREAS, the certificate of incorporation and by-laws of Holdings in effect
immediately following the Effective Time (as hereinafter defined) contain
provisions identical to the certificate of incorporation and by-laws of the
Company in effect immediately prior to the Effective Time (to the extent
required under Section 251(g)(4) of the DGCL);

WHEREAS, the directors and executive officers of the Company immediately prior
to the Effective Time will be the directors and executive officers of Holdings
upon the Effective Time;

WHEREAS, the boards of directors of Holdings, the Company and Merger Sub have
duly approved this Agreement and declared its advisability; and

WHEREAS, the Company, in its capacity as the sole stockholder of Holdings, and
Holdings, in its capacity as the sole stockholder of Merger Sub, have approved
this Agreement and the transactions contemplated thereby.

NOW, THEREFORE, in consideration of the mutual agreements herein contained, the
parties hereto agree as follows:

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ARTICLE I.

The Merger

1.1 Basic Transaction. Subject to the terms and provisions of this Agreement,
and in accordance with Section 251(g) of the DGCL, at the Effective Time, Merger
Sub shall be merged with and into the Company (the “Merger”), whereupon the
separate existence of Merger Sub shall cease in accordance with the provisions
of the DGCL, and the Company shall be the surviving corporation (the “Surviving
Corporation”). At the Effective Date, the effects of the Merger shall be as
provided in Section 259 of the DGCL.

1.2 Effective Time. The parties hereto shall cause this Agreement to be properly
executed and delivered for filing in accordance with the DGCL on the date
hereof. The Merger shall become effective upon the acceptance for record of this
Agreement by the Secretary of State of the State of Delaware in accordance with
the DGCL (the “Effective Time”).

ARTICLE II.

Conversion and Exchange of Shares

2.1 Conversion of Capital Stock. At the Effective Time and by virtue of the
Merger, and without any action on the part of the holders of shares of capital
stock of the Company, Holdings or Merger Sub:

(a) Each share of capital stock of the Company held by the Company as treasury
stock or owned by Merger Sub or any subsidiary of either of them immediately
prior to the Effective Time, shall be canceled, and no payment shall be made
with respect thereto;

(b) Each share of capital stock of Holdings owned by the Company or any
subsidiary thereof immediately prior to the Effective Time, shall be canceled,
and no payment shall be made with respect thereto;

(c) Each share of capital stock of Merger Sub outstanding immediately prior to
the Effective Time shall be converted into and become one share of capital stock
of the Surviving Corporation with the same rights and privileges as the shares
so converted and shall constitute the only outstanding shares of capital stock
of the Surviving Corporation; and

(d) Each share of Company Common Stock outstanding immediately prior to the
Effective Time shall, except as otherwise provided in clause (a) above, be
converted into the right to receive one (1) share of Holdings Common Stock
(subject to any restrictions applicable to the share of Company Common Stock,
e.g., outstanding unvested shares of restricted stock).

2.2 Rights of Certificate Holders. From and after the Effective Time, holders of
certificates formerly evidencing shares of Company Common Stock shall cease to
have any rights as stockholders of the Company, except as provided by law and
except that such holders shall have the rights set forth in Section 2.3 below.

 

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2.3 No Surrender of Certificates. Until thereafter surrendered for transfer or
exchange, each stock certificate that, immediately prior to the Effective Time,
evidenced outstanding Company Common Stock shall be deemed and treated for all
corporate purposes to evidence the ownership of the number of shares of Holdings
Common Stock into which such shares of Company Common Stock were converted
pursuant to the provisions of Section 2.1 above.

2.4 Conversion of Options.

(a) At the Effective Time, each option, whether or not exercisable, to purchase
shares of Company Common Stock which is then outstanding and unexercised (a
“Company Option”) shall cease to represent a right to acquire shares of Company
Common Stock and shall be converted automatically into an option to acquire,
under the same terms and conditions including exercise price, as were applicable
to such Company Option immediately prior to the Effective Time, shares of
Holdings Common Stock, and Holdings shall assume each Company Option and each
option plan or agreement pursuant to which such Company Option was granted. The
number of shares of Holdings Common Stock purchasable upon exercise of such
Company Option shall be equal to the number of shares of Company Common Stock
that were purchasable under such Company Option immediately prior to the
Effective Time. The terms of each Company Option shall, in accordance with its
terms, be subject to adjustment as appropriate to reflect any Change in
Capitalization (as defined in the applicable plan or agreement) with respect to
Holdings Common Stock on or subsequent to the Effective Time.

(b) At the Effective Time, each outstanding restricted stock unit (RSU) to
acquire shares of Company Common Stock shall be automatically converted into an
RSU to acquire, under the same terms and conditions, shares of Holdings Common
Stock and Holding shall assume each RSU and each plan or agreement pursuant to
which such RSU was granted.

(c) At the Effective Time, Holdings shall assume all other rights to acquire, or
to receive a distribution of, Company Common Stock, and such rights shall
automatically be converted into a right to acquire, or to receive a distribution
of, Holdings Common Stock under the same terms and conditions.

(d) At or prior to the Effective Date, Holdings shall reserve for issuance the
number of shares of Holdings Common Stock necessary to satisfy Holdings’
obligations under Section 2.4(a).

ARTICLE III.

The Surviving Corporation

3.1 Certificate of Incorporation. The certificate of incorporation of the
Company as in force and effect immediately prior to the Effective Time in the
State of Delaware shall be the certificate of incorporation of the Surviving
Corporation, except as follows:

(a) Article I thereof shall be amended so as to read in its entirety as follows:

“The name of the Corporation is Old ABI, Inc.”

 

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(b) A new Article XII shall be added thereto which shall be and read in its
entirety as follows:

“Any act or transaction by or involving the Corporation, other than the election
or removal of directors, that requires for its adoption under the DGCL or its
certificate of incorporation the approval of the stockholders of the
Corporation, shall, pursuant to subsection (7)(i)(A) of Section 251(g) of the
DGCL, require, in addition, the approval of the stockholders of Acuity Brands
Holdings, Inc. (or any successor by merger), by the same vote as is required by
the DGCL and/or the certificate of incorporation of the Corporation.”

3.2 Bylaws. The bylaws of the Company shall be amended in the Merger to be
identical to the bylaws of Merger Sub as in force and effect immediately prior
to the Effective Time, and shall be the bylaws of the Surviving Corporation
until changed, altered, or amended as therein provided and in the manner
prescribed by the provisions of the laws of the State of Delaware.

3.3 Directors and Officers. The directors and officers of Merger Sub immediately
prior to the Effective Time shall be the members of the Board of Directors and
the officers of the Surviving Corporation, all of whom shall hold their
respective offices until the election and qualification of their respective
successors or until their tenure is otherwise terminated in accordance with the
bylaws of the Surviving Corporation.

ARTICLE IV.

Covenants

4.1 Rights Plan. Prior to the Effective Time, (a) the Company shall take all
actions necessary to terminate, as of the Effective Time, the Stockholder
Protection Rights Agreement (the “Company Rights Plan”), between the Company and
The Bank of New York (as successor to Wells Fargo Bank Minnesota, N.A.), as
rights agent, dated as of November 12, 2001, and (b) Holdings shall take all
actions necessary to enter into a new rights agreement with substantially the
same terms as the Company Rights Plan.

4.2 Additional Actions. If, at any time after the Effective Time, the Surviving
Corporation shall consider or be advised that any further assignments or
assurances in law or any other acts are necessary or desirable (a) to vest,
perfect or confirm, of record or otherwise, in the Surviving Corporation, title
to and possession of any property or right of Merger Sub acquired or to be
acquired by reason of, or as a result of, the Merger, or (b) otherwise to carry
out the purpose of this Agreement, Merger Sub and the proper officers thereof
shall be deemed to have granted hereby to the Surviving Corporation an
irrevocable power of attorney to execute and deliver all such proper deeds,
assignments and assurances in law and to do all acts necessary or proper to
vest, perfect or confirm title to and the possession of such property or rights
in the Surviving Corporation and otherwise to carry out the purposes of this
Agreement; and the proper officers and directors of the Surviving Corporation
are hereby fully authorized in the name of Merger Sub or otherwise to take any
and all such action.

 

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ARTICLE V.

Amendment; Termination

5.1 Amendment. This Agreement may be amended only by the Board of Directors of
the parties hereto by a writing executed by each of the parties hereto;
provided, however, that there shall be no amendments which (a) alter or change
any term of the certificate of incorporation of the Surviving Corporation,
except for alterations or changes that could otherwise be adopted by the Board
of Directors of the Surviving Corporation; or (b) alter or change any of the
terms and conditions of this Agreement if such alteration or change would
adversely affect the holders of any class of stock of any of the parties hereto.

5.2 Termination. At any time prior to the Effective Time, this Agreement may be
terminated and the Merger may be abandoned by the Board of Directors of the
parties hereto.

5.3 Effect of Termination. If this Agreement is terminated pursuant to
Section 5.2 hereof, this Agreement shall become null and void and of no further
force and effect, and all obligations of the parties hereto shall terminate and
there shall be no liability or obligation of any party hereto or its
representatives.

ARTICLE VI.

Miscellaneous

6.1 Counterparts. This Agreement may be executed in one or more counterparts,
each of which shall be deemed to be an original and the same agreement.

6.2 Assignment. This Agreement shall be binding upon and inure to the benefit of
the successors and assigns of each party hereto.

6.3 Waivers. Any waiver by any party of any violation of, breach of, or default
under, any provision of this Agreement, or any other agreements provided for
herein, by any other party shall not be construed as, or constitute a continuing
waiver of such provision, or wavier of any other violation of, breach of, or
default under, any other provision of this Agreement or such other agreements.

6.4 Severability. In case any provision in this Agreement shall be held invalid,
illegal or unenforceable, the validity, legality and enforceability of the
remaining provisions hereof will not in any way be affected or impaired thereby.

[Signature Page Follows]

 

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IN WITNESS WHEREOF, each of the parties hereto has caused this Agreement to be
duly executed and attested hereto by its duly authorized officers as of the day
and year first above written.

 

COMPANY:

 

ACUITY BRANDS, INC.

By:  

/s/ Kenyon W. Murphy

Name:   Kenyon W. Murphy Title:   Executive Vice President, Chief Administrative
Officer and General Counsel

HOLDINGS:

 

ACUITY BRANDS HOLDINGS, INC.

By:  

/s/ Richard K. Reece

Name:   Richard K. Reece Title:   Executive Vice President and Chief Financial
Officer

MERGER SUB:

 

ACUITY MERGER SUB, INC.

By:  

/s/ Kenyon W. Murphy

Name:   Kenyon W. Murphy Title:   Executive Vice President, Chief Administrative
Officer and General Counsel

[Signature Page to the Agreement and Plan of Merger]

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Certificate of the Secretary of

Acuity Brands, Inc.

The undersigned, being the Secretary of Acuity Brands, Inc., a Delaware
corporation (the “Company”), hereby certifies that the Agreement and Plan of
Merger to which this certificate is attached has been adopted by the board of
directors of the Company pursuant to Section 251(g) of the DGCL and that the
conditions specified in the first sentence of Section 251(g) of the DGCL have
been satisfied.

 

/s/ Helen D. Haines

Helen D. Haines Secretary