JOINT FILING AGREEMENT

          In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, the persons named below agree to the joint filing on behalf of each of them of a Statement on Schedule 13G (including amendments thereto) with respect to the common stock of APPROACH RESOURCES INC. and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filings. In evidence thereof each of the undersigned, being duly authorized, hereby execute this Agreement on the date set forth below.

Date: February 13, 2008

	YORKTOWN ENERGY PARTNERS V, L.P.
	By:	Yorktown V Company LLC,
		Its General Partner
	By:	/s/ W. Howard Keenan, Jr.
		Name:	W. Howard Keenan, Jr.
		Title:	Managing Member
	YORKTOWN V COMPANY LLC
	By:	/s/ W. Howard Keenan, Jr.
		Name:	W. Howard Keenan, Jr.
		Title:	Managing Member