1 Exhibit 24.1 DIRECTOR AND/OR OFFICER OF PENTON MEDIA, INC. REGISTRATION STATEMENT ON FORM S-4 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS, that each of the undersigned directors and/or officers of Penton Media, Inc., a Delaware corporation (the "Company"), hereby constitutes and appoints Thomas L. Kemp, Daniel J. Ramella, Joseph G. NeCastro 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 resubstitution, for each of the undersigned and in the name, place and stead of each of the undersigned, to sign and file with the Securities and Exchange Commission under the Securities Act of 1933 (the "Securities Act") one or more Registration Statement(s) on Form S-4 relating to the registration of the Company's 10 3/8% Senior Subordinated Notes due 2011, with any and all amendments, supplements and exhibits thereto, including pre-effective and post-effective amendments or supplements, with full power and authority to do and perform any and all acts and things whatsoever required, necessary or desirable to be done in the premises, hereby ratifying and approving the act of said attorneys and any of them and any such substitute. 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 25th day of September 2001. /s/ Thomas L. Kemp /s/ R. Douglas Greene /s/ Richard B. Swank ------------------------ ------------------------ ------------------------ Thomas L. Kemp R. Douglas Greene Richard B. Swank Chief Executive Officer & Director Director Director /s/ Joseph G. NeCastro /s/ King W. Harris /s/ Paul W. Brown ------------------------ ------------------------ ------------------------ Joseph G. NeCastro King W. Harris Paul W. Brown Chief Financial Officer & Treasurer Director Director /s/ Jocelyn A. Bradford /s/ Daniel J. Ramella /s/ John J. Meehan ------------------------ ------------------------ ------------------------ Jocelyn A. Bradford Daniel J. Ramella John J. Meehan Vice President & Controller Director Director /s/ William B. Summers /s/ Edward J. Schwartz /s/ David B. Nussbaum ------------------------ ------------------------ ------------------------ William B. Summers Edward J. Schwartz David B. Nussbaum Director Director Director /s/ William J. Friend /s/ Don E. Schultz ------------------------ ------------------------ William J. Friend Don E. Schultz Director Director