1

                                                                     Exhibit 5.1



                           JONES, DAY, REAVIS & POGUE
                                   NORTH POINT
                               901 LAKESIDE AVENUE
                           CLEVELAND, OHIO 44114-1190
                             TELEPHONE: 216-586-3939


                                October 5, 2001

Penton Media, Inc.
1300 East Ninth Street
Cleveland, Ohio  44114

Ladies and Gentlemen:

     We are acting as counsel to Penton Media, Inc., a Delaware corporation (the
"Company"), in connection with (i) the offer to exchange (the "Senior
Subordinated Note Exchange Offer") $1,000 principal amount at maturity of the
Company's 10 3/8% Senior Subordinated Notes due 2011 (the "Exchange Notes") for
each $1,000 principal amount at maturity of the Company's outstanding 10 3/8%
Senior Subordinated Notes due 2011 (the "Private Notes") and (ii) the
preparation of the prospectus (the "Prospectus") contained in the registration
statement on Form S-4 (the "Registration Statement") filed on September 25, 2001
with the Securities and Exchange Commission by the Company for the purpose of
registering the Exchange Notes under the Securities Act of 1933 (the "Act"). The
Private Notes have been, and the Exchange Notes will be, issued pursuant to an
Indenture, dated as of June 28, 2001 (the "Indenture"), between the Company and
The Bank of New York, as Trustee.

     In rendering this opinion, we have examined such documents and records,
including an examination of originals or copies certified or otherwise
identified to our satisfaction, and matters of law we have deemed necessary for
purposes of this opinion.

     Based upon the foregoing and subject to the qualifications and limitations
stated herein, we are of the opinion that:

               (1) The Exchange Notes and the Guarantees by the Guarantors
endorsed thereon have been duly authorized.

               (2) When the Exchange Notes, substantially in the form as set
forth on an exhibit to the Indenture as filed as Exhibit 4.1 to the Registration
Statement, have been duly executed by the Company and authenticated by the
Trustee in accordance with the Indenture and duly delivered in exchange for the
Private Notes in accordance with the Senior Subordinated Note Exchange Offer in
the manner described in the Registration Statement:

                    (a) the Exchange Notes will be valid and binding obligations
     of the Company and will be entitled to the benefits of the Indenture; and

                    (b) the Guarantees by the Guarantors endorsed on the
     Exchange Notes will be valid and binding obligations of the Guarantors and
     will be entitled to the benefits of the Indenture.

     Our examination of matters of law in connection with the opinions expressed
herein has been limited to, and accordingly our opinions herein are limited to,
the laws of the State of New York, which are expressed to govern the Exchange
Notes, and the General Corporation Law of the State of Delaware, including the
applicable provisions of the Delaware Constitution and the reported judicial
decisions interpreting such law. We express no opinion with respect to any other
law of the State of Delaware or any other jurisdiction.

     We hereby consent to the filing of this opinion as Exhibit 5.1 to the
Registration Statement and the reference to us under the caption "Legal Matters"
in the Prospectus constituting a part of the Registration Statement. In giving
such consent, we do not thereby admit that we are included in the category of
persons whose consent is required under Section 7 of the Act or the rules and
regulations of the Securities and Exchange Commission promulgated thereunder.


                                           Very truly yours,



                                           /s/ Jones, Day, Reavis & Pogue