Virginia Treatment Center S-4 Registration of securities issued in business combination transactions

Exhibit 3.2.31

CERTIFICATE OF INCORPORATION

OF

NSC ACQUISITION CORP.

FIRST: The name of the corporation is:

NSC Acquisition Corp.

SECOND: The address of its registered office in the State of Delaware is 15 East North Street in the City of Dover, County of Kent Zip Code 19901. The name of its registered agent at such address is Incorporating Services, Ltd.

THIRD: The nature of the business or purposes to be conducted or promoted is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of Delaware.

FOURTH: The corporation is authorized to issue one class of stock, to be designated “Common Stock,” with a par value of $0.0001 per share. The total number of shares of Common Stock that the corporation shall have authority to issue is 1,000.

FIFTH: The business and affairs of the corporation shall be managed by or under the direction of the Board of Directors. In addition to the powers and authority expressly conferred upon them by statute or by this Certificate of Incorporation or the Bylaws of the corporation; the directors are hereby empowered to exercise all such powers and do all such acts and things as may be exercised or done by the corporation. Election of directors need not be by written ballot, unless the Bylaws so provide.

SIXTH: The Board of Directors is authorized to make, adopt, amend, alter or repeal the Bylaws of the corporation. The stockholders shall also have power to make, adopt, amend, alter or repeal the Bylaws of the corporation.

SEVENTH: The name and mailing address of the incorporator is:

Kathryn Clamar

Gray Cary Ware & Freidenrich LLP

153 Townsend Street, Suite 800

San Francisco, CA 94107-1922

EIGHTH: To the fullest extent permitted by the Delaware General Corporation Law, as the same exists or may hereafter be amended, a director of the corporation shall not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director. Any repeal or modification of the foregoing provisions of this Article EIGHTH by the stockholders of the corporation shall not adversely affect any right or protection of a director of the corporation existing at the time of, or increase the liability of any director of the corporation with respect to any acts or omissions occurring prior to, such repeal or modification.

THE UNDERSIGNED, being the incorporator hereinbefore named, for the purpose of forming a corporation pursuant to the General Corporation Law of Delaware, does make this certificate, hereby declaring and certifying that this is my act and deed and the facts herein stated are true, and accordingly have hereunto set my hand this 30th day of June, 2003.

/s/ Kathryn Clamar

Kathryn Clamar Incorporator

CERTIFICATE OF CHANGE OF LOCATION OF REGISTERED OFFICE

AND OF REGISTERED AGENT

It is hereby certified that:

1. The name of the corporation (hereinafter called the “Corporation”) is NSC ACQUISITION CORP.

2. The registered office of the Corporation within the State of Delaware is hereby changed to 160 Greentree Drive, Suite 101, City of Dover, 19904, County of Kent.

3. The registered agent of the Corporation within the State of Delaware is hereby changed to National Registered Agents, Inc., the business office of which is identical with the registered office of the corporation as hereby changed.

4. The Corporation has authorized the changes hereinbefore set forth by resolution of its Board of Directors.

Signed on: May 3, 2005.

/s/ Pamela Burke

Pamela Burke, Secretary