AGREEMENT AND PLAN OF MERGER

Exhibit 10.1

AGREEMENT AND PLAN OF MERGER

THIS AGREEMENT AND PLAN OF MERGER (this “Agreement”) is entered into on this 25^th 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:

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.