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                                                                   Exhibit 3.1.1

                            CERTIFICATE OF AMENDMENT

                                       OF

                        THE CERTIFICATE OF INCORPORATION

                                       OF

                          ADVANSTAR COMMUNICATIONS INC.

                     Pursuant to Section 805 of the Business
                    Corporation Law of the State of New York


         Advanstar Communications Inc., a New York corporation (hereinafter
called the "CORPORATION"), does hereby certify as follows:

         (1) The name of the Corporation is Advanstar Communications Inc. The
Corporation was formed under the name of HBJ Publications, Inc.

         (2) The Certificate of Incorporation of the Corporation was originally
filed with the Department of State of New York on January 23, 1987.

         (3) Paragraph FOURTH of the Corporation's Certificate of Incorporation,
which sets forth the aggregate number of shares that the Corporation shall have
the authority to issue, is hereby amended to increase the Corporation's unissued
stock from 500,000 unissued shares of common stock with a par value of one cent
($.01) per share to 2,500,000 shares of unissued shares consisting of 2,000,000
shares of unissued preferred stock with a par value of one cent ($.01) per share
and 500,000 shares of unissued common stock with a par value of one cent ($.01)
per share. No change has been made to the number of issued shares of stock.
Paragraph FOURTH is further amended to provide that the preferred stock will
have such rights, preferences and limitations as may be subsequently determined
by the Board of Directors, and to set out the relative rights of the holders of
the Corporation's common stock. To effect the foregoing amendments, paragraph
FOURTH shall be amended to read as follows:

         "FOURTH: The total number of shares of stock that the corporation shall
have authority to issue is three million five hundred thousand (3,500,000), of
which two million (2,000,000) shall be shares of Preferred Stock ("Preferred
Shares") with a par value of one cent ($.01) per share and one million five
hundred thousand (1,500,000)
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shall be shares of Common Stock ("Common Shares") with a par value of one cent
($.01) per share.

         (1) The relative rights, preferences and limitations of the Preferred
Shares and Common Shares, respectively, are as follows:

         (a) The Preferred Shares may be issued from time to time in one or more
series of any number of shares, provided that the aggregate number of shares
issued and not cancelled of any and all such series shall not exceed the total
number of shares of Preferred Shares hereinabove authorized, and with
distinctive serial designations, all as shall hereafter be stated and expressed
in the resolution or resolutions providing for the issue of such shares of
Preferred Shares from time to time adopted by the Board pursuant to authority so
to do which is hereby vested in the Board.

         Each series of Preferred Shares (i) may have such voting powers, full
or limited, or may be without voting powers; (ii) may be subject to redemption
at such time or times and at such prices; (iii) may be entitled to receive
dividends (which may be cumulative or non-cumulative) at such rate or rates, on
such conditions and at such times, and payable in preference to, or in such
relation to, the dividends payable on any other class or classes or series of
shares; (iv) may have such rights upon the dissolution of, or upon any
distribution of the assets of, the Corporation; (v) may be made convertible into
or exchangeable for, shares of any other class or classes or of any other series
of the same or any other class or classes of shares of the Corporation at such
price or prices or at such rates of exchange and with such adjustments; (vi) may
be entitled to the benefit of a sinking fund to be applied to the purchase or
redemption of shares of such series in such amount or amounts; (vii) may be
entitled to the benefit of conditions and restrictions upon the creation of
indebtedness of the Corporation or any subsidiary, upon the issue of any
additional shares (including additional shares of such series or of any other
series) and upon the payment of dividends or the making of other distributions
on, and the purchase, redemption or other acquisition by the Corporation or any
subsidiary of, any outstanding shares of the Corporation and (viii) may have
such other relative, participating, optional or other special rights,
qualifications, limitations or restrictions thereof; all as shall be stated in
said resolution or resolutions providing for the issue of such Preferred Shares.
Preferred Shares of any series that have been redeemed (whether through the
operation of a sinking fund or otherwise) or that, if convertible or
exchangeable, have been converted into or exchanged for shares of any other
class or classes shall have the status of authorized and unissued Preferred
Shares of the same series and may be reissued as a part of the series of which
they were originally a part or may be reclassified and reissued as part of a new
series of Preferred Shares to be created by resolution or resolutions of the
Board or as part of any other series of Preferred Shares, all subject to the
conditions or restrictions on issuance set

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forth in the resolution or resolutions adopted by the Board providing for the
issue of any series of Preferred Shares.

         (b) Subject to the provisions of any applicable law or of the By-laws
of the Corporation, as from time to time amended, with respect to the closing of
the transfer books or the fixing of a record date for the determination of
shareholders entitled to vote, and except as otherwise provided by law or by the
resolution or resolutions providing for the issue of any series of Preferred
Shares, the holders of outstanding Common Shares shall exclusively possess
voting power for the election of directors and for all other purposes, each
holder of record of Common Shares being entitled to one vote for each Common
Share standing in his or her name on the books of the Corporation. Except as
otherwise provided by the resolution or resolutions providing for the issue of
any series of Preferred Shares, the holders of Common Shares shall be entitled,
to the exclusion of the holders of Preferred Shares of any and all series, to
receive such dividends as from time to time may be declared by the Board. In the
event of any liquidation, dissolution or winding up of the Corporation, whether
voluntary or involuntary, after payment shall have been made to the holders of
Preferred Shares of the full amount to which they shall be entitled pursuant to
the resolution or resolutions providing for the issue of any series of Preferred
Shares, the holders of Common Shares shall be entitled, to the exclusion of the
holders of Preferred Shares of any and all series, to share, ratably according
to the number of Common Shares held by them, in all remaining assets of the
Corporation available for distribution to its share holders.

         (4) The foregoing amendment was duly authorized, in accordance with
Section 803 of the Business Corporation Law of the State of New York (the "BCL")
pursuant to a unanimous written consent of the Board of Directors of the
Corporation, adopted in accordance with Section 708 of the BCL, and a written
consent of the sole stockholder of the Corporation, adopted in accordance with
Section 615 of the BCL.


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         IN WITNESS WHEREOF, Advanstar Communications Inc. has caused this
Certificate to be duly executed in its corporate name this 1st day of February,
2001.

                                            ADVANSTAR COMMUNICATIONS, INC.


                                            By:/s/ James M. Alic
                                               ---------------------------------
                                               Name:
                                               Title:


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