Exhibit 10.3.1

FIRST AMENDMENT

THIS FIRST AMENDMENT, dated as of March 22, 2002 (this "Amendment"), is among ADVANSTAR
COMMUNICATIONS INC., a New York corporation (the "Borrower") and the Lenders (as defined below) signatories hereto.

W I T N E S S E T H:

WHEREAS, the Borrower, various financial institutions from time to time parties thereto (collectively, the "Lenders"), Credit Suisse First Boston (as successor in
interest to DLJ Capital Funding, Inc.), as Lead Arranger and Syndication Agent, Fleet National Bank, as Administrative Agent, and Barclays Bank PLC, as Documentation Agent, are parties to the
Amended and Restated Credit Agreement, dated as of November 7, 2000 (as amended, supplemented, amended and restated or otherwise modified prior to the date hereof, the
"Existing Credit Agreement");

WHEREAS,
the Borrower has requested that the Lenders amend the Existing Credit Agreement in certain respects as more specifically set forth herein; and

WHEREAS,
the Lenders have agreed, subject to the terms and conditions set forth herein, to amend the Existing Credit Agreement as set forth below (the Existing Credit Agreement, as
amended by this Amendment, being referred to as the "Credit Agreement");

NOW,
THEREFORE, in consideration of the agreements herein contained, and for other valuable consideration the receipt of which is hereby acknowledged, the parties hereto hereby agree as
follows.

PART I  DEFINITIONS

SUBPART
1.1.Certain Definitions.The following terms (whether or not underscored) when used in this Amendment
shall have the following meanings (such meanings to be equally applicable to the singular and plural form thereof):

"Amendment" is defined in the preamble.

"Credit Agreement" is defined in the third recital.

"Existing Credit Agreement" is defined in the first recital.

"First Amendment Effective Date" is defined in Subpart 3.1.

SUBPART
1.2.Other Definitions.Terms for which meanings are provided in the Existing Credit Agreement are,
unless otherwise defined herein or the context otherwise requires, used in this Amendment with such meanings.

PART II  AMENDMENTS TO THE  EXISTING CREDIT AGREEMENT

Subject to the terms of Part III, effective on the First Amendment Effective Date the Existing Credit Agreement is hereby amended in accordance with this
Part.

SUBPART
2.1.Amendments to Article I.Article I of the Existing Credit Agreement is hereby amended
as set forth inSubparts 2.1.1and2.1.2.

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SUBPART
2.1.1.Section 1.1 of the Existing Credit Agreement is hereby amended by inserting the following
definitions in such Section in the appropriate alphabetical order:

"First Amendment" means the First Amendment, dated as of March 22, 2002, among the Borrower and the Lenders parties thereto.

"First Amendment Effective Date" is defined in Subpart 3.1 of the First Amendment.

"Senior Secured Bank Debt" means the Obligations owing under this Agreement.

"Senior Secured Bank Debt Rating" means, as of any date, the rating of the Borrower's Senior Secured Bank Debt, as issued by S&P and
Moody's in their rating reports.

SUBPART
2.1.2.The definition of "Applicable Margin" appearing in Section 1.1 of the Existing Credit
Agreement is hereby amended as follows:





Leverage Ratio

Applicable Margin For Base
Rate Loans

Applicable Margin For LIBO
Rate Loansgreater than 5.5:1

2.00
%
3.25
%greater than 5.0:1 and less than
or equal to 5.5:1

1.75
%
3.00
%greater than 4.5:1 and less
than or equal to 5.0:1

1.50
%
2.75
%greater than 4.0:1 and less
than or equal to 4.5:1

1.25
%
2.50
%greater than 3.5:1 and less
than or equal to 4.0:1

0.75
%
2.00
%less than or equal to 3.5:1

0.50
%
1.75
%


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SUBPART
2.2.Amendment to Article VII.The grid in clause (a) of Section 7.2.4 of the
Existing Credit Agreement is hereby amended in its entirety as follows:

Period

Leverage RatioClosing Date to 03/31/01

6.50:104/01/01 to 09/30/01

6.25:110/01/01 to 12/31/01

5.90:101/01/02 to 03/31/02

6.90:104/01/02 to 12/31/02

6.75:101/01/03 to 03/31/03

6.50:104/01/03 to 06/30/03

6.25:107/01/03 to 09/30/03

6.00:110/01/03 to 12/31/03

5.75:101/01/04 to 03/31/04

4.50:104/01/04 to 09/30/04

4.25:110/01/04 and thereafter

4.00:1


PART III  CONDITIONS TO EFFECTIVENESS

SUBPART
3.1.Effective Date and Conditions.This Amendment shall become effective on the date (the
"First Amendment Effective Date") when each of the conditions set forth in this Part have been satisfied. The Administrative Agent shall provide written
notice to the Borrower of the occurrence of the First Amendment Effective Date promptly following the occurrence thereof.

SUBPART
3.1.1.Execution of Counterparts.The Administrative Agent shall have received counterparts of this
Amendment duly executed and delivered on behalf of the Borrower and the Required Lenders.

SUBPART
3.1.2.Affirmation and Consent.The Administrative Agent shall have received, with counterparts for each
Lender, a duly executed copy of an Affirmation and Consent, dated as of the First Amendment Effective Date, in form and substance satisfactory to the Administrative Agent, duly executed and delivered
by each of the Obligors other than the Borrower.

SUBPART
3.1.3.Amendment Fees, Expenses, etc.The Administrative Agent shall have received for the account of
each Lender, an amendment fee in an amount equal to 0.25% of the sum of (i) such Lender's Revolving Loan Commitment Amount plus (ii) the outstanding principal amount of Term Loans owing
to such Lender, but such fees shall be payable only to each Lender that has unconditionally delivered (including by way of facsimile) its executed signature page to this Amendment to the attention of
Kate Kelly, Esq. at Mayer, Brown, Rowe & Maw, 1675 Broadway, New York, New York 10019 (19th floor), telecopy number 212-262-1910 at or prior to 5:00 p.m. (New
York time) on March 21, 2002.

SUBPART
3.1.4.Legal Details, etc.All documents executed or submitted pursuant hereto shall be reasonably
satisfactory in form and substance to the Administrative Agent and its counsel. The Administrative Agent and its counsel shall have received all information, and such counterpart originals or such
certified or other copies of such materials, as the Administrative Agent or its counsel may

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reasonably request. All legal matters incident to the transactions contemplated by this Amendment shall be reasonably satisfactory to the Administrative Agent and its counsel.

PART IV  MISCELLANEOUS PROVISIONS

SUBPART
4.1.Cross-References.References in this Amendment to any Part or Subpart are, unless otherwise
specified, to such Part or Subpart of this Amendment.

SUBPART
4.2.Loan Document Pursuant to Existing Credit Agreement.This Amendment is a Loan Document executed
pursuant to the Existing Credit Agreement and shall be construed, administered and applied in accordance with all of the terms and provisions of the Existing Credit Agreement.

SUBPART
4.3.Successors and Assigns.This Amendment shall be binding upon and inure to the benefit of the
parties hereto and their respective successors and assigns.

SUBPART
4.4.Full Force and Effect; Limited Amendment.Except as expressly amended hereby, all of the
representations, warranties, terms, covenants, conditions and other provisions of the Existing Credit Agreement and the Loan Documents shall remain unchanged and shall continue to be, and shall
remain, in full force and effect in accordance with their respective terms. The amendments set forth herein shall be limited precisely as provided for herein to the provisions expressly amended herein
and shall not be deemed to be an amendment to, waiver of, consent to or modification of any other term or provision of the Existing Credit Agreement, any other Loan Document referred to therein or
herein or of any transaction or further or future action on the part of the Borrower or any Obligor which would require the consent of the Lenders under the Existing Credit Agreement or any of the
Loan Documents.

SUBPART
4.5.Governing Law.THIS AMENDMENT SHALL BE DEEMED TO BE A CONTRACT MADE UNDER
AND GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW YORK (INCLUDING FOR SUCH PURPOSES SECTION 5-1401 AND 5-1402 OF THE GENERAL OBLIGATIONS LAW OF THE STATE OF NEW
YORK).

SUBPART
4.6.Execution in Counterparts.This Amendment may be executed in any number of counterparts by the
parties hereto, each of which counterparts when so executed shall be an original, but all the counterparts shall together constitute one and the same agreement.

SUBPART
4.7.Representations and Warranties.In order to induce the Lenders to execute and deliver this
Amendment the Borrower hereby represents and warrants to the Lenders that after giving effect to this
Amendment, all of the statements set forth in Section 5.2.1 (except clause (b)) of the Existing Credit Agreement are true and correct.

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IN
WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed by their respective officers hereunto duly authorized as of the day and year first above written.

| |  | ADVANSTAR COMMUNICATIONS INC.
| |  | -----------------------------
| |  | By:                          
| |  |                              
| |  | By:                          

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