EXHIBIT 24 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS: THAT, WHEREAS, SBC COMMUNICATIONS INC., a Delaware corporation, hereinafter referred to as the "Corporation," proposes to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, an annual report on Form 10-K; and WHEREAS, the undersigned is an officer and a director of the Corporation; NOW, THEREFORE, the undersigned hereby constitutes and appoints James D. Ellis, Donald E. Kiernan, Liam S. Coonan, Roger W. Wohlert, or any one of them, all of the City of San Antonio and State of Texas, his attorneys for him and in his name, place and stead, and in each of his offices and capacities in the Corporation, to execute and file such annual report, and thereafter to execute and file any amendment or amendments thereto, hereby giving and granting to said attorneys full power and authority to do and perform each and every act and thing whatsoever requisite and necessary to be done in and concerning the premises, as fully to all intents and purposes as the undersigned might or could do if personally present at the doing thereof, hereby ratifying and confirming all that said attorneys may or shall lawfully do, or cause to be done, by virtue hereof. IN WITNESS WHEREOF, the undersigned executed this Power of Attorney the 28th day of January 2000. /s/ Edward E. Whitacre, Jr. Edward E. Whitacre, Jr. Chairman of the Board, Director and Chief Executive Officer EXHIBIT 24 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS: THAT, WHEREAS, SBC COMMUNICATIONS INC., a Delaware corporation, hereinafter referred to as the "Corporation," proposes to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, an annual report on Form 10-K; and WHEREAS, the undersigned is an officer and a director of the Corporation; NOW, THEREFORE, the undersigned hereby constitutes and appoints Edward E. Whitacre, Jr., James D. Ellis, Donald E. Kiernan, Liam S. Coonan, Roger W. Wohlert, or any one of them, all of the City of San Antonio and State of Texas, his attorneys for him and in his name, place and stead, and in each of his offices and capacities in the Corporation, to execute and file such annual report, and thereafter to execute and file any amendment or amendments thereto, hereby giving and granting to said attorneys full power and authority to do and perform each and every act and thing whatsoever requisite and necessary to be done in and concerning the premises, as fully to all intents and purposes as the undersigned might or could do if personally present at the doing thereof, hereby ratifying and confirming all that said attorneys may or shall lawfully do, or cause to be done, by virtue hereof. IN WITNESS WHEREOF, the undersigned executed this Power of Attorney the 28th day of January 2000. /s/ Royce S. Caldwell Royce S. Caldwell Vice Chairman of the Board, Director and President-SBC Operations EXHIBIT 24 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS: THAT, WHEREAS, SBC COMMUNICATIONS INC., a Delaware corporation, hereinafter referred to as the "Corporation," proposes to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, an annual report on Form 10-K; and WHEREAS, the undersigned is an officer of the Corporation; NOW, THEREFORE, the undersigned hereby constitutes and appoints Edward E. Whitacre, Jr., James D. Ellis, Liam S. Coonan, Roger W. Wohlert, or any one of them, all of the City of San Antonio and State of Texas, his attorneys for him and in his name, place and stead, and in each of his offices and capacities in the Corporation, to execute and file such annual report, and thereafter to execute and file any amendment or amendments thereto, hereby giving and granting to said attorneys full power and authority to do and perform each and every act and thing whatsoever requisite and necessary to be done in and concerning the premises, as fully to all intents and purposes as the undersigned might or could do if personally present at the doing thereof, hereby ratifying and confirming all that said attorneys may or shall lawfully do, or cause to be done, by virtue hereof. IN WITNESS WHEREOF, the undersigned executed this Power of Attorney the 28th day of January 2000. /s/ D. E. Kiernan - ----------------- D. E. Kiernan Senior Executive Vice President, Chief Financial Officer and Treasurer EXHIBIT 24 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS: THAT, WHEREAS, SBC COMMUNICATIONS INC., a Delaware corporation, hereinafter referred to as the "Corporation," proposes to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, an annual report on Form 10-K; and WHEREAS, the undersigned is a director of the Corporation; NOW, THEREFORE, the undersigned hereby constitutes and appoints Edward E. Whitacre, Jr., James D. Ellis, Donald E. Kiernan, Liam S. Coonan, Roger W. Wohlert, or any one of them, all of the City of San Antonio and State of Texas, the undersigned's attorneys for the undersigned and in the undersigned's name, place and stead, and in the undersigned's office and capacity in the Corporation, to execute and file such annual report, and thereafter to execute and file any amendment or amendments thereto, hereby giving and granting to said attorneys full power and authority to do and perform each and every act and thing whatsoever requisite and necessary to be done in and concerning the premises, as fully to all intents and purposes as the undersigned might or could do if personally present at the doing thereof, hereby ratifying and confirming all that said attorneys may or shall lawfully do, or cause to be done, by virtue hereof. IN WITNESS WHEREOF, the undersigned executed this Power of Attorney the 28th day of January 2000. /s/ Clarence C. Barksdale /s/ James E. Barnes - ---------------------------- --------------------------- Clarence C. Barksdale James E. Barnes Director Director /s/ August A. Busch III /s/ Ruben R. Cardenas - ---------------------------- --------------------------- August A. Busch III Ruben R. Cardenas Director Director EXHIBIT 24 POWER OF ATTORNEY PAGE 2 /s/ William P. Clark /s/ Martin K. Eby, Jr. - ---------------------------- --------------------------- William P. Clark Martin K. Eby, Jr. Director Director /s/ Herman E. Gallegos /s/ Jess T. Hay - ---------------------------- --------------------------- Herman E. Gallegos Jess T. Hay Director Director /s/ James A. Henderson /s/ Bobby R. Inman - ---------------------------- --------------------------- James A. Henderson Bobby R. Inman Director Director /s/ Charles F. Knight /s/ Lynn M. Martin - ---------------------------- --------------------------- Charles F. Knight Lynn M. Martin Director Director /s/ John B. McCoy /s/ Mary S. Metz - ---------------------------- --------------------------- John B. McCoy Mary S. Metz Director Director /s/ Toni Rembe /s/ S. Donley Ritchey - ---------------------------- --------------------------- Toni Rembe S. Donley Ritchey Director Director /s/ Joyce M. Roche /s/ Richard M. Rosenberg - ---------------------------- --------------------------- Joyce M. Roche Richard M. Rosenberg Director Director /s/ Carlos Slim Helu /s/ Laura D'Andrea Tyson - ---------------------------- --------------------------- Carlos Slim Helu Laura D'Andrea Tyson Director Director /s/ Patricia P. Upton - ---------------------------- Patricia P. Upton Director