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                                                                      Exhibit 24

                          DIRECTORS AND/OR OFFICERS OF
                               PENTON MEDIA, INC.

                           ANNUAL REPORT ON FORM 10-K

                                POWER OF ATTORNEY

KNOW ALL MEN BY THERE PRESENTS, that each of the undersigned directors and
officers of Penton Media, Inc., a Delaware corporation, hereby constitutes and
appoints Thomas L. Kemp, Daniel J. Ramella, and Preston L. Vice, and each of
them, as the true and lawful attorney-in-fact or attorneys-in-fact, with full
power of substitution and revocation, for each of the undersigned and in the
name, place and stead of each of the undersigned, to sign on behalf of each of
the undersigned an Annual Report on Form 10-K for the fiscal year ended December
31, 2003 pursuant to Section 13 of the Securities and Exchange Act of 1934 and
to sign any and all amendments to such Annual Report, and to file the same, with
all exhibits thereto, and other documents in connection therewith, including,
without limitation, a Form 12b-25, with the Securities and Exchange Commission,
granting to said attorney-in-fact or attorneys-in-fact, and each of them, full
power and authority to do so and perform each and every act and thing requisite
and necessary to be done in and about the premises, as fully to all intents and
purposes as the undersigned might or could do in person, hereby ratifying and
confirming all that said attorney-in-fact or attorneys-in-fact or any of them or
their substitute or substitutes, may lawfully do or cause to be done by virtue
hereof.

This Power of Attorney may be executed in multiple counterparts, each of which
shall be deemed an original with respect to the person executing it.

Executed as of this 30th day of March 2004.
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<S>                                            <C>
/s/ THOMAS L. KEMP                             /s/ KING HARRIS
--------------------------------------------   ---------------------------------------
Thomas L. Kemp                                 King Harris
Chairman and Chief Executive Officer           Director
and Director
(Principal Executive Officer)

/s/ PRESTON L. VICE                            /s/ WILLIAM B. SUMMERS
--------------------------------------------   ---------------------------------------
Preston L. Vice                                William B. Summers
Chief Financial Officer, Secretary             Director
and Controller
(Principal Financial and Accounting Officer)

/s/ VINCENT D. KELLY                           /s/ DANIEL J. RAMELLA
--------------------------------------------   ---------------------------------------
Vincent D. Kelly                               Daniel J. Ramella
Director                                       Director

/s/ DANIEL C. BUDDE                            /s/ EDWARD J. SCHWARTZ
--------------------------------------------   ---------------------------------------
Daniel C. Budde                                Edward J. Schwartz
Director                                       Director

/s/ PENI A. GARBER                             /s/ HANNAH C. CRAVEN
--------------------------------------------   ---------------------------------------
Peni A. Garber                                 Hannah C. Craven
Director                                       Director

/s/ R. DOUGLAS GREENE                          /s/ PERRY A. SOOK
--------------------------------------------   ---------------------------------------
R. Douglas Greene                              Perry A. Sook
Director                                       Director
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