EXHIBIT 3.4

                         AMENDED AND RESTATED BY-LAWS

                           ADVANSTAR HOLDINGS, INC.


                           ARTICLE I - STOCKHOLDERS
                           ---------   ------------

     Section 1.  Annual Meeting.
     ---------   -------------- 

     An annual meeting of the stockholders, for the election of directors to
succeed those whose terms expire and for the transaction of such other business
as may properly come before the meeting, shall be held at such place, on such
date, and at such time as the Board of Directors shall each year fix, which date
shall be within thirteen months subsequent to the later of the date of
incorporation or the last annual meeting of stockholders.

     Section 2.  Special Meetings.
     ---------   ---------------- 

     Special meetings of the stockholders, for any purpose or purposes
prescribed in the notice of the meeting, may be called by the Board of Directors
or the chief executive officer and shall be held at such place, on such date,
and at such time as they or he or she shall fix.

     Section 3.  Notice of Meetings.
     ---------   ------------------ 

     Written notice of the place, date, and time of all meetings of the
stockholders shall be given, not less than ten nor more than sixty days before
the date on which the meeting is to be held, to each stockholder entitled to
vote at such meeting, except as otherwise provided herein or required by law
(meaning, here and hereinafter, as required from time to time by the Delaware
General Corporation Law or the Certificate of Incorporation of the Corporation).

     When a meeting is adjourned to another place, date or time, written notice
need not be given of the adjourned meeting if the place, date and time thereof
are announced at the meeting at which the adjournment is taken; provided,
however, that if the date of any adjourned meeting is more than thirty days
after the date for which the meeting was originally noticed, or if a new record
date is fixed for the adjourned meeting, written notice of the place, date, and
time of the adjourned meeting shall be given in conformity herewith.  At any
adjourned meeting, any business may be transacted which might have been
transacted at the original meeting.

     Section 4.  Quorum.
     ---------   ------ 

     At any meeting of the stockholders, the holders of a majority of all of the
shares of the stock entitled to vote at the meeting, present in person or by
proxy, shall constitute a quorum for all purposes, unless or except to the
extent that the presence of a larger number may be required by law.

 
                                      -2-

     If a quorum shall fail to attend any meeting, the chairman of the meeting
or the holders of a majority of the shares of stock entitled to vote who are
present, in person or by proxy, may adjourn the meeting to another place, date,
or time.

     If a notice of any adjourned special meeting of stockholders is sent to all
stockholders entitled to vote thereat, stating that it will be held with those
present constituting a quorum, then except as otherwise required by law, those
present at such adjourned meeting shall constitute a quorum, and all matters
shall be determined by a majority of the votes cast at such meeting.

     Section 5.  Organization.
     ---------   ------------ 

     Such person as the Board of Directors may have designated or, in the
absence of such a person, the chief executive officer of the Corporation or, in
his or her absence, such person as may be chosen by the holders of a majority of
the shares entitled to vote who are present, in person or by proxy, shall call
to order any meeting of the stockholders and act as chairman of the meeting.  In
the absence of the Secretary of the Corporation, the secretary of the meeting
shall be such person as the chairman appoints.

     Section 6.  Conduct of Business.
     ---------   ------------------- 

     The chairman of any meeting of stockholders shall determine the order of
business and the procedure at the meeting, including such regulation of the
manner of voting and the conduct of discussion as seem to him or her in order.

     Section 7.  Proxies and Voting.
     ---------   ------------------ 

     At any meeting of the stockholders, every stockholder entitled to vote may
vote in person or by proxy authorized by an instrument in writing filed in
accordance with the procedure established for the meeting.

     Each stockholder shall have one vote for every share of stock entitled to
vote which is registered in his or her name on the record date for the meeting,
except as otherwise provided herein or required by law.

     All voting, including on the election of directors but excepting where
otherwise required by law, may be a voice vote; provided, however, that upon
demand therefore by a stockholder entitled to vote or his or her proxy, a stock
vote shall be taken.  Every stock vote shall be taken by ballots, each of which
shall state the name of the stockholder or proxy voting and such other
information as may be required under the procedure established for the meeting.
Every vote taken by ballots shall be counted by an inspector or inspectors
appointed by the chairman of the meeting.

     All elections shall be determined by a plurality of the votes cast, and
except as otherwise required by law, all other matters shall be determined by a
majority of the votes cast.

 
                                      -3-

     Section 8.  Stock List.
     ---------   ---------- 

     A complete list of stockholders entitled to vote at any meeting of
stockholders, arranged in alphabetical order for each class of stock and showing
the address of each such stockholder and the number of shares registered in his
or her name, shall be open to the examination of any such stockholder, for any
purpose germane to the meeting, during ordinary business hours for a period of
at least ten (10) days prior to the meeting, either at a place within the city
where the meeting is to be held, which place shall be specified in the notice of
the meeting, or if not so specified, at the place where the meeting is to be
held.

     The stock list shall also be kept at the place of the meeting during the
whole time thereof and shall be open to the examination of any such stockholder
who is present.  This list shall presumptively determine the identity of the
stockholders entitled to vote at the meeting and the number of shares held by
each of them.

     Section 9.  Consent of Stockholders in Lieu of Meeting.
     ---------   ------------------------------------------ 

     Any action required to be taken at any annual or special meeting of
stockholders of the Corporation, or any action which may be taken at any annual
or special meeting of the stockholders, may be taken without a meeting, without
prior notice and without a vote, if a consent in writing, setting forth the
action so taken, shall be signed by the holders of outstanding stock having not
less than the minimum number of votes that would be necessary to authorize or
take such action at a meeting at which all shares entitled to vote thereon were
present and voted.

                        ARTICLE II - BOARD OF DIRECTORS
                        ----------   ------------------

     Section 1.  Number and Term of Office.
     ---------   ------------------------- 

     The number of directors who shall constitute the whole board shall be such
number as the Board of Directors shall at the time have designated, except that
in the absence of any such designation, such number shall be four (4).  Each
director shall be elected for a term of one year and until his or her successor
is elected and qualified, except as otherwise provided herein or required by
law.

     Whenever the authorized number of directors is increased between annual
meetings of the stockholders, a majority of the directors then in office shall
have the power to elect such new directors for the balance of a term and until
their successors are elected and qualified.  Any decrease in the authorized
number of directors shall not become effective until the expiration of the term
of the directors then in office unless, at the time of such decrease, there
shall be vacancies on the board which are being eliminated by the decrease.

     Section 2.  Vacancies.
     ---------   --------- 

     If the office of any director becomes vacant by reason of death,
resignation, disqualification, removal or other cause, a majority of the
directors remaining in office, although 

 
                                      -4-

less than a quorum may elect a successor for the unexpired term and until his or
her successor is elected and qualified.

     Section 3.  Regular Meetings.
     ---------   ---------------- 

     Regular meetings or of the Board of Directors shall be held at such place
or places, on such date or dates, and at such time or times as shall have been
established by the Board of Directors and publicized among all directors.  A
notice of each regular meeting shall not be required.

     Section 4.  Special Meetings.
     ---------   ---------------- 

     Special meetings of the Board of Directors may be called by one-third of
the directors then in office (rounded up to the nearest whole number) or by the
chief executive officer and shall be held at such place, on such date, and at
such time as they or he or she shall fix.  Notice of the place, date, and time
of each such special meeting shall be given each director by whom it is not
waived by mailing written notice not less than five days before the meeting or
by telegraphing the same not less than twenty-four hours before the meeting.
Unless otherwise indicated in the notice thereof, any and all business may be
transacted at a special meeting.

     Section 5.  Quorum.
     ---------   ------ 

     At any meeting of the Board of Directors, a majority of the total number of
the whole Board shall constitute a quorum for all purposes.  If a quorum shall
fail to attend any meeting, a majority of those present may adjourn the meeting
to another place, date, or time, without further notice or waiver thereof.

     Section 6.  Participation in Meetings By Conference Telephone.
     ---------   ------------------------------------------------- 

     Members of the Board of Directors, or of any committee thereof, may
participate in a meeting of such Board or committee by means of conference
telephone or similar communications equipment by means of which all persons
participating in the meeting can hear each other and such participation shall
constitute presence in person at such meeting.

     Section 7.  Conduct of Business.
     ---------   ------------------- 

     At any meeting of the Board of Directors, business shall be transacted in
such order and manner as the Board may from time to time determine, and all
matters shall be determined by the vote of a majority of the directors present,
except as otherwise provided herein or required by law.  Action may be taken by
the Board of Directors without a meeting if all members thereof consent thereto
in writing, and the writing or writings are filed with the minutes of
proceedings of the Board of Directors.

 
                                      -5-

     Section 8.  Powers.
     ---------   ------ 

     The Board of Directors may, except as otherwise required by law, exercise
all such powers and do all such acts and things as may be exercised or done by
the Corporation, including, without limiting the generality of the foregoing,
the unqualified power:

          (1) To declare dividends from time to time in accordance with law;

          (2) To purchase or otherwise acquire any property, rights or
privileges on such terms as it shall determine;

          (3) To authorize the creation, making and issuance, in such form as it
may determine, of written obligations of every kind, negotiable or non-
negotiable, secured or unsecured, and to do all things necessary in connection
therewith;

          (4) To remove any officer of the Corporation with or without cause,
and from time to time to devolve the powers and duties of any officer upon any
other person for the time being;

          (5) To confer upon any officer of the Corporation the power to
appoint, remove and suspend subordinate officers, employees and agents;

          (6) To adopt from time to time such stock, option, stock purchase,
bonus or other compensation plans for directors, officers, employees and agents
of the Corporation and its subsidiaries as it may determine;

          (7) To adopt from time to time such insurance, retirement, and other
benefit plans for directors, officers, employees and agents of the Corporation
and its subsidiaries as it may determine; and

          (8) To adopt from time to time regulations, not inconsistent with
these by-laws, for the management of the Corporation's business and affairs.

     Section 9.  Compensation of Directors.
     ---------   ------------------------- 

     Directors, as such, may receive, pursuant to resolution of the Board of
Directors, fixed fees and other compensation for their services as directors,
including, without limitation, their services as members of committees of the
Board of Directors.

                           ARTICLE III - COMMITTEES
                           -----------   ----------

     Section 1.  Committees of the Board of Directors.
     ---------   ------------------------------------ 

     The Board of Directors, by a vote of a majority of the whole Board, may
from time to time designate committees of the Board, with such lawfully
delegable powers and duties as it 

 
                                      -6-

thereby confers, to serve at the pleasure of the Board and shall, for those
committees and any others provided for herein, elect a director or directors to
serve as the member or members, designating, if it desires, other directors as
alternate members who may replace any absent or disqualified member at any
meeting of the committee. Any committee so designated may exercise the power and
authority of the Board of Directors to declare a dividend or to authorize the
issuance of stock if the resolution which designates the committee or a
supplemental resolution of the Board of Directors shall so provide. In the
absence or disqualification of any member of any committee and any alternate
member in his place, the member or members of the committee present at the
meeting and not disqualified from voting, whether or not he or she or they
constitute a quorum, may by unanimous vote appoint another member of the Board
of Directors to act at the meeting in the place of the absent or disqualified
member.

     Section 2.  Conduct of Business.
     ---------   ------------------- 

     Each committee may determine the procedural rules for meeting and
conducting its business and shall act in accordance therewith, except as
otherwise provided herein or required by law.  Adequate provision shall be made
for notice to members of all meetings; one-third of the members shall constitute
a quorum unless the committee shall consist of one or two members, in which
event one member shall constitute a quorum; and all matters shall be determined
by a majority vote of the members present.  Action may be taken by any committee
without a meeting if all members thereof consent thereto in writing, and the
writing or writings are filed with the minutes of the proceedings of such
committee.

                             ARTICLE IV - OFFICERS
                             ----------   --------

     Section 1.  Generally.
     ---------   --------- 

     The officers of the Corporation shall consist of a President, one or more
Vice Presidents, a Secretary, a Treasurer and such other officers as may from
time to time be appointed by the Board of Directors.  Officers shall be elected
by the Board of Directors, which shall consider that subject at its first
meeting after every annual meeting of stockholders.  Each officer shall hold
office until his or her successor is elected and qualified or until his or her
earlier resignation or removal.  The President shall be a member of the Board of
Directors.  Any number of offices may be held by the same person.

     Section 2.  President.
     ---------   --------- 

     The President shall be the chief executive officer of the Corporation.
Subject to the provisions of these by-laws and to the direction of the Board of
Directors, he or she shall have the responsibility for the general management
and control of the business and affairs of the Corporation and shall perform all
duties and have all powers which are commonly incident to the office of chief
executive or which are delegated to him or her by the Board of Directors.  He or
she shall have the power to sign all stock certificates, contracts and other
instruments of the Corporation which are authorized and shall have general
supervision and direction of all of the other officers, employees and agents of
the Corporation.

 
                                      -7-

     Section 3.  Vice President.
     ---------   -------------- 

     Each Vice President shall have such powers and duties as may be delegated
to him or her by the Board of Directors.  One Vice President shall be designated
by the Board to perform the duties and exercise the powers of the President in
the event of the President's absence or disability.

     Section 4.  Treasurer.
     ---------   --------- 

     The Treasurer shall have the responsibility for maintaining the financial
records of the Corporation and shall have custody of all monies and securities
of the Corporation.  He or she shall make such disbursements of the funds of the
Corporation as are authorized and shall render from time to time an account of
all such transactions and of the financial condition of the Corporation.  The
Treasurer shall also perform such other duties as the Board of Directors may
from time to time prescribe.

     Section 5.  Secretary.
     ---------   --------- 

     The Secretary shall issue all authorized notices for, and shall keep
minutes of, all meetings of the stockholders and the Board of Directors.  He or
she shall have charge of the corporate books and shall perform such other duties
as the Board of Directors may from time to time prescribe.

     Section 6.  Delegation of Authority.
     ---------   ----------------------- 

     The Board of Directors may from time to time delegate the powers or duties
of any officer to any other officers or agents, notwithstanding any provision
hereof.

     Section 7.  Removal.
     ---------   ------- 

     Any officer of the Corporation may be removed at any time, with or without
cause, by the Board of Directors.

     Section 8.  Action with Respect to Securities of Other Corporations.
     ---------   ------------------------------------------------------- 

     Unless otherwise directed by the Board of Directors, the President or any
officer of the Corporation authorized by the President shall have power to vote
and otherwise act on behalf of the Corporation, in person or by proxy, at any
meeting of stockholders of or with respect to any action of stockholders of any
other corporation in which this Corporation may hold securities and otherwise to
exercise any and all rights and powers which this Corporation may possess by
reason of its ownership of securities in such.

 
                                      -8-

                          ARTICLE V - INDEMNIFICATION
                          ---------   ---------------

     Section 1.  Indemnification of Directors, Officers, Employees and Agents.
     ---------   ------------------------------------------------------------ 

     Any person who was or is a party or s threatened to be made a party to any
threatened, pending or completed action, suit or proceeding, whether civil,
criminal, administrative or investigative (including any action or suit by or in
the right of the Corporation to procure a judgment in its favor) by reason of
the fact that he or she is or was a director, officer, employee or agent of the
Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise (including, without limitation, employee
benefit plans), shall be indemnified by the Corporation, if, as and to the
extent authorized by applicable law, against expenses (including attorney's
fees), judgments, fines (including, without limitation, any excise taxes
assessed on a person with respect to any employee benefit plan) and amounts paid
in settlement actually and reasonably incurred by him or her in connection with
the defense or settlement of such action, suit or proceeding.  Expenses incurred
by an officer or director in defending a civil or criminal action, suit or
proceeding shall be paid by the Corporation in advance of the final disposition
of such action, suit or proceeding upon receipt of an undertaking by or on
behalf of such director or officer to repay such amount if it shall ultimately
be determined that he is not entitled to be indemnified by the Corporation as
authorized by statute.  Such expenses incurred by other employees and agents may
be so paid upon such terms and conditions, if any, as the Board of Directors
deemed appropriate.  The indemnification and advancement of expenses provided
by, or granted pursuant to, this By-law or statute in a specific case shall not
be deemed exclusive of any other rights to which any person seeking
indemnification or advancement of expenses may be entitled under any lawful
agreement, vote of stockholders or disinterested directors or otherwise, both as
to action in his or her official capacity and as to action in another capacity
while holding such office, and shall continue as to a person who has ceased to
be a director, officer, employee or agent and shall inure to the benefit of the
heirs, executors and administrators of such a person.

                              ARTICLE VI  - STOCK
                              -----------   -----

     Section 1.  Certificates of Stock.
     ---------   --------------------- 

     Each stockholder shall be entitled to a certificate signed by, or in the
name of the Corporation by, the President or a Vice President, and by the
Secretary or an Assistant Secretary, or the Treasurer or an Assistant Treasurer,
certifying the number of shares owned by him or her.  Any of or all the
signatures on the certificate may be facsimile.

     Section 2.  Transfer of Stock.
     ---------   ----------------- 

     Transfers of stock shall be made only upon the transfer books of the
Corporation kept at an office of the Corporation or by transfer agents
designated to transfer shares of the stock of the Corporation.  Except where a
certificate is issued in accordance with Section 1 of Article V of 

 
                                      -9-

these by-laws, an outstanding certificate for the number of shares involved
shall be surrendered for cancellation before a new certificate is issued
therefore.

     Section 3.  Record Date.
     ---------   ----------- 

     The Board of Directors may fix a record date, which shall not be more than
sixty nor less than ten days before the date of any meeting of stockholders, nor
more than sixty days prior to the time for the other action hereinafter
described, as of which there shall be determined the stockholders who are
entitled: to notice of or to vote at any meeting of stockholders or any
adjournment thereof; to express consent to corporate action in writing without a
meeting; to receive payment of any dividend or other distribution or allotment
of any rights; or to exercise any rights with respect to any change, conversion
or exchange  of stock or with respect to any other lawful action.

     Section 4.  Lost, Stolen or Destroyed Certificates.
     ---------   -------------------------------------- 

     In the event of the loss, theft or destruction of any certificate of stock,
another may be issued in its place pursuant to such regulations as the Board of
Directors may establish concerning proof of such loss, theft or destruction and
concerning the giving of a satisfactory bond or bonds of indemnity.

     Section 5.  Regulations.
     ---------   ----------- 

     The issue, transfer, conversion and registration of certificates of stock
shall be governed by such other regulations as the Board of Directors may
establish.

                             ARTICLE VII - NOTICES
                             -----------   -------

     Section 1.  Notices.
     ---------   ------- 

     Except as otherwise specifically provided herein or required by law, all
notices required to be given to any stockholder, director, officer, employee or
agent shall be in writing and may in every instance be effectively given by hand
delivery to the recipient thereof, by depositing such notice in the mails,
postage paid, or by sending such notice by prepaid telegram or mailgram.  Any
such notice shall be addressed to such stockholder, director, officer, employee
or agent at his or her last know address as the same appears on the books of the
Corporation.  The time when such notice is received, if hand delivered, or
dispatched, if delivered through the mails or by telegram or mailgram, shall be
the time of the giving of the notice.

     Section 2.  Waivers.
     ---------   ------- 

     A written waiver of any notice, signed by a stockholder, director, officer,
employee or agent, whether before or after the time of the event for which
notice is to be given, shall be deemed equivalent to the notice required to be
given to such stockholder, director, officer, 

 
                                      -10-

employee or agent. Neither the business nor the purpose of any meeting need be
specified in such a waiver.

                          ARTICLE VII - MISCELLANEOUS
                          -----------   -------------

     Section 1.  Facsimile Signatures.
     ---------   -------------------- 

     In addition to the provisions for use of facsimile signatures elsewhere
specifically authorized in these by-laws, facsimile signatures of any officer or
officers of the Corporation may be used whenever and as authorized by the Board
of Directors or a committee thereof.

     Section 2.  Corporate Seal.
     ---------   -------------- 

     The Board of Directors may provide a suitable seal, containing the name of
the Corporation, which seal shall be in the charge of the Secretary.  If and
when so directed by the Board of Directors or a committee thereof, duplicates of
the seal may be kept and used by the Treasurer or by an Assistant Secretary or
Assistant Treasurer.

     Section 3.  Reliance upon Books, Reports and Records.
     ---------   ---------------------------------------- 
 
     Each director, each member of any committee designated by the Board of
Directors, and each officer of the Corporation shall, in the performance of his
duties, be fully protected in relying in good faith upon the books of account or
other records of the Corporation, including reports made to the Corporation by
any of its officers, by an independent certified public accountant, or by an
appraiser selected with reasonable care.

     Section 4.  Fiscal Year.
     ---------   ----------- 

     The fiscal year of the Corporation shall be as fixed by the Board of
Directors.

     Section 5.  Time Periods.
     ---------   ------------ 

     In applying any provisions of these by-laws which require that an act be
done or not done a specified number of days prior to an event or that an act be
done during a period of a specified number of days prior to an event, calendar
days shall be used, the day of the doing of the act shall be excluded, and the
day of the event shall be included.

                            ARTICLE IX - AMENDMENTS
                            ----------   ----------

     These by-laws may be amended or repealed by the Board of Directors at any
meeting or by the stockholders at any meeting.