EXHIBIT 99.1

JOINT FILING AGREEMENT

     In accordance with Rule 13d-1(k)(1)(iii) under the Securities Exchange Act of 1934, as amended, each of the persons named below agrees to the joint filing of a Statement on Schedule 13D (including amendments thereto) with respect to the common stock, $0.01 par value per share, of HCA Inc., a corporation incorporated under the laws of the State of Delaware, and further agrees that this Joint Filing Agreement be included as an exhibit to such filings; provided, that, as contemplated by Section 13d-1(k)(1)(ii), no person shall be responsible for the completeness or accuracy of the information concerning the other persons making the filing, unless such person knows or has reason to believe that such information is inaccurate.

[signature pages follow]

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

Merrill Lynch Professional Clearing Corp.		Merrill Lynch, Pierce, Fenner & Smith Incorporated
By:	/s/ Eileen M. Porter	By:	/s/ Eileen M. Porter
	Name:  Eileen M. Porter		Name:  Eileen M. Porter
	Title:  Authorized Person*		Title:  Authorized Person*
Merrill Lynch Financial Markets, Inc.		Merrill Lynch International
By:	/s/ Eileen M. Porter	By:	/s/ Eileen M. Porter
	Name:  Eileen M. Porter		Name:  Eileen M. Porter
	Title:  Authorized Person*		Title:  Authorized Person*
Merrill Lynch & Co., Inc.		Merrill Lynch Trust Company, FSB
By:	/s/ Eileen M. Porter	By:	/s/ Eileen M. Porter
	Name:  Eileen M. Porter		Name:  Eileen M. Porter
	Title:  Authorized Person*		Title:  Authorized Person*

* See attached Powers of Attorney

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

FRISCO, INC.
By:	/s/ Patricia Champion Frist
	Name: Patricia Champion Frist
	Title: President
FRISCO PARTNERS
By:	/s/ Thomas F. Frist, Jr.
	Name: Thomas F. Frist, Jr.
	Title: General Partner

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

/s/ Thomas F. Frist, Jr.

Thomas F. Frist, Jr.

     IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

/s/ Patricia Champion Frist

Patricia Champion Frist

     IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

/s/ Patricia Frist Elcan

Patricia Frist Elcan

     IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

/s/ William Robert Frist

William Robert Frist

     IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

/s/ Thomas F. Frist, III

Thomas F. Frist, III

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

BANK OF AMERICA CORPORATION
NB HOLDINGS CORPORATION
By:	/s/ Charles F. Bowman
	Name: Charles F. Bowman
	Title: Senior Vice President

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

NATIONSBANC MONTGOMERY HOLDINGS
CORPORATION
By:	/s/ Robert Qutub
	Name: Robert Qutub
	Title: President

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

BANC OF AMERICA SECURITIES LLC
By:	/s/ Richard E. Konefal
	Name: Richard E. Konefal
	Title: Senior Vice President

          IN WITNESS WHEREOF, the undersigned has duly executed this Joint Filing Agreement as of this 3^rd day of August, 2006.

CITIGROUP INC.
By:	/s/ Ali L. Karshan
	Name:  Ali L. Karshan
	Title:  Assistant Secretary