<PAGE>

                                                                      Exhibit 24
                                                                      ----------



                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                             /s/ Jameson A. Baxter
                                             --------------------------
                                             Jameson A. Baxter
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                            /s/ Richard G. Cline
                                            ---------------------------
                                            Richard G. Cline
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                    /s/ Gary L. Crittenden
                                    --------------------------------
                                    Gary L. Crittenden
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                    /s/ James A. Henderson
                                    -----------------------------
                                    James A. Henderson
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                    /s/ Gregory P. Josefowicz
                                    -------------------------------
                                    Gregory P. Josefowicz
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                    /s/ Neil S. Novich
                                    --------------------------
                                    Neil S. Novich
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 7/th/ day of March,
2000.



                                    /s/ Jerry K. Pearlman
                                    --------------------------
                                    Jerry K. Pearlman
<PAGE>

                               RYERSON TULL, INC.

                               POWER OF ATTORNEY



     KNOW ALL MEN BY THESE PRESENTS, that I, the undersigned, as a director
and(or) officer of Ryerson Tull, Inc., a Delaware corporation, do hereby
nominate, constitute and appoint Jay M. Gratz, Neil S. Novich, Terence R. Rogers
and Joyce E. Mims, or any one or more of them, my true and lawful attorneys and
agents to do any and all acts and things and execute any and all instruments
which said attorneys and agents, or any of them, may deem necessary or advisable
to enable said Ryerson Tull, Inc. to comply with the Securities Exchange Act of
1934, as amended, and any requirements of the Securities and Exchange Commission
in respect thereof, in connection with the preparation and filing of the Annual
Report on Form 10-K of said Ryerson Tull, Inc. for the fiscal year ended
December 31, 1999, including specifically, but without limitation thereof, full
power and authority to sign my name as a director and(or) officer of said
Ryerson Tull, Inc. to said Annual Report on Form 10-K and any amendment thereto,
hereby ratifying and confirming all that said attorneys and agents, or any of
them, shall do or cause to be done by virtue thereof.

     IN WITNESS WHEREOF, I have hereunto set my hand this 17/th/ day of January,
2000.



                                    /s/ Ronald L. Thompson
                                    -------------------------------
                                    Ronald L. Thompson