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                                                                      EXHIBIT 24

                                POWER OF ATTORNEY
       For Executing Forms 3, 4 and 5, Form 144 and Schedules 13D and 13G

     Know all by these presents, that the undersigned hereby constitutes and
appoints J. Ross Craft as the undersigned's true and lawful attorney-in-fact to:

     (1)  execute for and on behalf of the undersigned, (a) in the undersigned's
          capacity as an officer, designated insider and/or director of Approach
          Resources Inc. (the "Company"), Forms 3, 4 and 5 in accordance with
          Section 16(a) of the Securities Exchange Act of 1934, as amended (the
          "Exchange Act"), and the rules promulgated thereunder (b) Form 144 and
          (c) Schedules 13D and 13G (including amendments thereto) in accordance
          with Sections 13(d) and 13(g) of the Exchange Act and the rules
          thereunder;

     (2)  do and perform any and all acts for and on behalf of the undersigned
          which may be necessary or desirable to complete and execute any such
          Form 3, 4 or 5, Form 144 or Schedules 13D or 13G (including amendments
          thereto) and timely file such forms or schedules with the United
          States Securities and Exchange Commission and any stock exchange,
          self-regulatory association or similar authority; and

     (3)  take any other action of any type whatsoever in connection with the
          foregoing which, in the opinion of such attorney-in-fact, may be of
          benefit to, in the best interest of, or legally required by, the
          undersigned, it being understood that the documents executed by such
          attorney-in-fact on behalf of the undersigned pursuant to this Power
          of Attorney shall be in such form and shall contain such terms and
          conditions as such signing attorney-in-fact may approve in his
          discretion.

     The undersigned hereby grants to such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or his
substitute or substitutes, shall lawfully do or cause to be done by virtue of
this Power of Attorney and the rights and powers herein granted. The undersigned
acknowledges that the foregoing attorney-in-fact, in serving in such capacity at
the request of the undersigned, is not assuming, nor is the Company assuming,
any of the undersigned's responsibilities to comply with Section 16 of the
Securities Exchange Act of 1934.

     The undersigned agrees that such attorney-in-fact may rely entirely on
information furnished orally or in writing by the undersigned to the
attorney-in-fact. The undersigned also agrees to indemnify and hold harmless the
Company and such attorney-in-fact against any losses, claims, damages or
liabilities (or actions in these respects) that arise out of or are based upon
any untrue statements or omissions of necessary facts in the information
provided by the undersigned to such attorney-in-fact for purposes of executing,
acknowledging, delivering or filing Form 3, 4 or 5, Form 144 or Schedule 13D or
13G (including amendments thereto) and agrees to reimburse the Company and the
attorney-in-fact on demand for any legal or other expenses reasonably incurred
in connection with investigating or defending against any such loss, claim,
damage, liability or action.

     This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4 and 5, Form 144 and
Schedules 13D and 13G (including amendments thereto) with respect to the
undersigned's holdings of and transactions in securities relating to the
Company, unless earlier revoked by the undersigned in a signed writing delivered
to the foregoing attorneys-in-fact. This Power of Attorney does not revoke any
other power of attorney that the undersigned has previously granted.

     IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of November 7, 2007.


                                        /s/ J. Curtis Henderson
                                        ----------------------------------------
                                        J. Curtis Henderson


