On December 6, 2012, Acadia Healthcare Company, Inc., a Delaware corporation ("Acadia" or the "Company"), entered into an underwriting agreement (the "Underwriting Agreement") with Merrill Lynch, Pierce, Fenner & Smith Incorporated, Citigroup Global Markets Inc. and Jefferies & Company, Inc., as representatives of the several underwriters named therein (collectively, the "Underwriters"), and the selling stockholders named therein (collectively, the "Selling Stockholders") in connection with the sale by Acadia and the Selling Stockholders (the "Offering") of an aggregate of 10,576,623 shares (the "Firm Shares") of Acadia's common stock, par value $0.01 per share ("Common Stock"), at a public offering price of $22.50 per share. The Firm Shares consist of 7,000,000 shares of Common Stock to be sold by Acadia and 3,576,623 shares of Common Stock to be sold, collectively, by the Selling Stockholders. Pursuant to the Underwriting Agreement, Acadia and certain of the Selling Stockholders have granted the Underwriters a 30-day option to purchase an aggregate of up to an additional 1,583,153 shares of Common Stock, which includes up to 1,050,000 additional shares from Acadia and up to 533,153 additional shares from certain of the Selling Stockholders.

The net proceeds to the Company, after underwriting discounts and commissions and estimated offering expenses and before giving effect to the Underwriters' option, if exercised, will be approximately $150.3 million. Acadia intends to use the net proceeds from the Offering principally to fund the Company's acquisition strategy, particularly the planned acquisitions of Behavioral Centers of America, LLC and AmiCare Behavioral Centers, LLC, and otherwise for general corporate purposes, which may include the repayment of debt under the Company's senior secured credit facility. Acadia will not receive any proceeds from the sale of shares of Common Stock by the Selling Stockholders. The closing of the sale of the Firm Shares is scheduled to occur on or about December 12, 2012.

The Underwriting Agreement contains customary representations, warranties, covenants and closing conditions. Pursuant to the Underwriting Agreement, Acadia and the Selling Stockholders agreed to indemnify the underwriters against certain liabilities that could be incurred by them in connection with the Offering. In connection with the Offering, the directors and executive officers of the Company and the Selling Stockholders have entered into 90-day "lock-up" agreements.

The Offering was made pursuant to a prospectus supplement and an accompanying prospectus filed with the Securities and Exchange Commission pursuant to Acadia's effective shelf registration statement on Form S-3 (File No. 333-184456).

On December 4, 2012, Acadia issued a press release announcing the commencement of the Offering, a copy of which is attached hereto as Exhibit 99.1 and incorporated herein by reference.

On December 7, 2012, Acadia issued a press release announcing the pricing of the Offering, a copy of which is attached hereto as Exhibit 99.2 and incorporated herein by reference.

(d) Exhibits

Exhibit
Number                                    Description

 1.1         Underwriting Agreement, dated December 6, 2012, by and among Acadia,
             the selling stockholders named in Schedule B thereof and Merrill
             Lynch, Pierce, Fenner & Smith Incorporated, Citigroup Global Markets
             Inc. and Jefferies & Company, Inc., as representatives of the several
             underwriters named therein

 5.1         Opinion of Waller Lansden Dortch & Davis, LLP

23.1         Consent of Waller Lansden Dortch & Davis, LLP (included in Exhibit
             5.1)

99.1         Press release of Acadia Healthcare Company, Inc., dated December 4,
             2012

99.2         Press release of Acadia Healthcare Company, Inc., dated December 7,
             2012