<PAGE>

                                                                      Exhibit 24
                                                                     Page 1 of 6
                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE PRESENTS:

         That the undersigned hereby irrevocably constitutes and appoints RHYS
J. BEST, CHARLES J. KESZLER AND ROBERT F. SPEARS, or any of them, as the true
and lawful agents and attorneys-in-fact of the undersigned (the
"Attorneys-in-Fact"), each with full power to appoint a substitute or
substitutes to act hereunder, to execute and deliver for and on behalf of the
undersigned the Annual Report of Lone Star Technologies, Inc. on Form 10-K
(including any amendments thereto) to be filed with the Securities and Exchange
Commission pursuant to the Securities Exchange Act of 1934 for the fiscal year
ended December 31, 1999. The undersigned hereby ratifies and confirms all that
the Attorneys-in-Fact, or any substitute or substitutes, may do by virtue of
this Power of Attorney.

         IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
at Dallas, Texas on this 21st day of March, 2000.



                                       /s/ CHARLES L. BLACKBURN
                                       ---------------------------
                                       Charles L. Blackburn


STATE OF TEXAS             )
                           )
COUNTY OF DALLAS           )

         BEFORE ME, Sharon E. Goodrich, a Notary Public in and for the State of
Texas, on this day did personally appear Charles L. Blackburn, known to me to be
the person whose name is subscribed to the foregoing Power of Attorney, and
acknowledged to me that he executed such Power of Attorney for the purposes and
consideration therein expressed.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, this 21st day of March, 2000.



                                       /s/ SHARON E. GOODRICH
                                       -----------------------------
                                       Notary Public, State of Texas



My Commission Expires:  9/14/02


<PAGE>


                                                                      Exhibit 24
                                                                     Page 2 of 6

                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE PRESENTS:

         That the undersigned hereby irrevocably constitutes and appoints RHYS
J. BEST, CHARLES J. KESZLER AND ROBERT F. SPEARS, or any of them, as the true
and lawful agents and attorneys-in-fact of the undersigned (the
"Attorneys-in-Fact"), each with full power to appoint a substitute or
substitutes to act hereunder, to execute and deliver for and on behalf of the
undersigned the Annual Report of Lone Star Technologies, Inc. on Form 10-K
(including any amendments thereto) to be filed with the Securities and Exchange
Commission pursuant to the Securities Exchange Act of 1934 for the fiscal year
ended December 31, 1999. The undersigned hereby ratifies and confirms all that
the Attorneys-in-Fact, or any substitute or substitutes, may do by virtue of
this Power of Attorney.

         IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
at Dallas, Texas on this 21st day of March, 2000.



                                       /s/ DEAN P. GUERIN
                                       ---------------------------------
                                       Dean P. Guerin


STATE OF TEXAS            )
                          )
COUNTY OF DALLAS          )

         BEFORE ME, Sharon E. Goodrich, a Notary Public in and for the State of
Texas, on this day did personally appear Dean P. Guerin, known to me to be the
person whose name is subscribed to the foregoing Power of Attorney, and
acknowledged to me that he executed such Power of Attorney for the purposes and
consideration therein expressed.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, this 21st day of March, 2000.



                                       /s/ SHARON E. GOODRICH
                                       ---------------------------------
                                       Notary Public, State of Texas



My Commission Expires:  9/14/02


<PAGE>


                                                                      Exhibit 24
                                                                     Page 3 of 6

                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE PRESENTS:

         That the undersigned hereby irrevocably constitutes and appoints RHYS
J. BEST, CHARLES J. KESZLER AND ROBERT F. SPEARS, or any of them, as the true
and lawful agents and attorneys-in-fact of the undersigned (the
"Attorneys-in-Fact"), each with full power to appoint a substitute or
substitutes to act hereunder, to execute and deliver for and on behalf of the
undersigned the Annual Report of Lone Star Technologies, Inc. on Form 10-K
(including any amendments thereto) to be filed with the Securities and Exchange
Commission pursuant to the Securities Exchange Act of 1934 for the fiscal year
ended December 31, 1999. The undersigned hereby ratifies and confirms all that
the Attorneys-in-Fact, or any substitute or substitutes, may do by virtue of
this Power of Attorney.

         IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
at Dallas, Texas on this 21st day of March, 2000.



                                       /s/ FREDERICK B. HEGI, JR.
                                       ---------------------------------
                                       Frederick B. Hegi, Jr.


STATE OF TEXAS          )
                        )
COUNTY OF DALLAS        )

         BEFORE ME, Sharon E. Goodrich, a Notary Public in and for the State of
Texas, on this day did personally appear Frederick B. Hegi, Jr., known to me to
be the person whose name is subscribed to the foregoing Power of Attorney, and
acknowledged to me that he executed such Power of Attorney for the purposes and
consideration therein expressed.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, this 21st day of March, 2000.



                                       /s/ SHARON E. GOODRICH
                                       ---------------------------------
                                       Notary Public, State of Texas



My Commission Expires:  9/14/02


<PAGE>


                                                                      Exhibit 24
                                                                     Page 4 of 6

                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE PRESENTS:

         That the undersigned hereby irrevocably constitutes and appoints RHYS
J. BEST, CHARLES J. KESZLER AND ROBERT F. SPEARS, or any of them, as the true
and lawful agents and attorneys-in-fact of the undersigned (the
"Attorneys-in-Fact"), each with full power to appoint a substitute or
substitutes to act hereunder, to execute and deliver for and on behalf of the
undersigned the Annual Report of Lone Star Technologies, Inc. on Form 10-K
(including any amendments thereto) to be filed with the Securities and Exchange
Commission pursuant to the Securities Exchange Act of 1934 for the fiscal year
ended December 31, 1999. The undersigned hereby ratifies and confirms all that
the Attorneys-in-Fact, or any substitute or substitutes, may do by virtue of
this Power of Attorney.

         IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
at Dallas, Texas on this 21st day of March, 2000.



                                       /s/ JAMES E. McCORMICK
                                       ---------------------------------
                                       James E. McCormick


STATE OF TEXAS          )
                        )
COUNTY OF DALLAS        )

         BEFORE ME, Sharon E. Goodrich, a Notary Public in and for the State of
Texas, on this day did personally appear James E. McCormick, known to me to be
the person whose name is subscribed to the foregoing Power of Attorney, and
acknowledged to me that he executed such Power of Attorney for the purposes and
consideration therein expressed.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, this 21st day of March, 2000.



                                       /s/ SHARON E. GOODRICH
                                       ---------------------------------
                                       Notary Public, State of Texas



My Commission Expires:  9/14/02

<PAGE>


                                                                Exhibit 24
                                                               Page 5 of 6

                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE PRESENTS:

         That the undersigned hereby irrevocably constitutes and appoints RHYS
J. BEST, CHARLES J. KESZLER AND ROBERT F. SPEARS, or any of them, as the true
and lawful agents and attorneys-in-fact of the undersigned (the
"Attorneys-in-Fact"), each with full power to appoint a substitute or
substitutes to act hereunder, to execute and deliver for and on behalf of the
undersigned the Annual Report of Lone Star Technologies, Inc. on Form 10-K
(including any amendments thereto) to be filed with the Securities and Exchange
Commission pursuant to the Securities Exchange Act of 1934 for the fiscal year
ended December 31, 1999. The undersigned hereby ratifies and confirms all that
the Attorneys-in-Fact, or any substitute or substitutes, may do by virtue of
this Power of Attorney.

         IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
at Dallas, Texas on this 21st day of March, 2000.



                                       /s/ M. JOSEPH McHUGH
                                       ---------------------------------
                                       M. Joseph McHugh


STATE OF TEXAS          )
                        )
COUNTY OF DALLAS        )

         BEFORE ME, Sharon E. Goodrich, a Notary Public in and for the State of
Texas, on this day did personally appear M. Joseph McHugh, known to me to be the
person whose name is subscribed to the foregoing Power of Attorney, and
acknowledged to me that he executed such Power of Attorney for the purposes and
consideration therein expressed.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, this 21st day of March, 2000.



                                       /s/ SHARON E. GOODRICH
                                       ---------------------------------
                                       Notary Public, State of Texas


My Commission Expires:  9/14/02



<PAGE>


                                                                      Exhibit 24
                                                                     Page 6 of 6

                                POWER OF ATTORNEY


KNOW ALL MEN BY THESE PRESENTS:

         That the undersigned hereby irrevocably constitutes and appoints RHYS
J. BEST, CHARLES J. KESZLER AND ROBERT F. SPEARS, or any of them, as the true
and lawful agents and attorneys-in-fact of the undersigned (the
"Attorneys-in-Fact"), each with full power to appoint a substitute or
substitutes to act hereunder, to execute and deliver for and on behalf of the
undersigned the Annual Report of Lone Star Technologies, Inc. on Form 10-K
(including any amendments thereto) to be filed with the Securities and Exchange
Commission pursuant to the Securities Exchange Act of 1934 for the fiscal year
ended December 31, 1999. The undersigned hereby ratifies and confirms all that
the Attorneys-in-Fact, or any substitute or substitutes, may do by virtue of
this Power of Attorney.

         IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
at Dallas, Texas on this 21st day of March, 2000.



                                       /s/ THOMAS M. MERCER, JR.
                                       ---------------------------------
                                       Thomas M. Mercer, Jr.


STATE OF TEXAS           )
                         )
COUNTY OF DALLAS         )

         BEFORE ME, Sharon E. Goodrich, a Notary Public in and for the State of
Texas, on this day did personally appear Thomas M. Mercer, Jr., known to me to
be the person whose name is subscribed to the foregoing Power of Attorney, and
acknowledged to me that he executed such Power of Attorney for the purposes and
consideration therein expressed.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, this 21st day of March, 2000.



                                       /s/ SHARON E. GOODRICH
                                       ---------------------------------
                                       Notary Public, State of Texas

My Commission Expires:  9/14/02