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                                                                   Exhibit 10.15

                              EMPLOYMENT AGREEMENT

     This EMPLOYMENT AGREEMENT ("AGREEMENT") made as of January 1, 1999, between
Penton Media, Inc. (formerly known as Penton Publishing, Inc.), a Delaware
corporation (the "COMPANY"), and James D. Atherton ("EXECUTIVE")

     In consideration of the mutual covenants contained herein and other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

     1. EMPLOYMENT. The Company shall employ Executive, and Executive accepts
continued employment with the Company as of the date hereof, upon the terms and
conditions set forth in this Agreement for the period beginning on the date
hereof and ending as provided in paragraph 5 hereof (the "EMPLOYMENT PERIOD").

     2. POSITION AND DUTIES.

     (a) During the Employment Period, Executive shall serve as a Group
President of the Company, with initial responsibility for the Company's
Mechanical Systems/Construction, Government/Compliance, Management, Supply
Chain/Aviation, Industrial Shows of America, and Ancillary Product Sales and
Marketing Groups (the "Division"), and shall have the normal duties,
responsibilities and authority of an executive serving in such position, subject
to the power of the Board of Directors of the Company (the "BOARD") or the Chief
Executive Officer of the Company to expand or limit such duties,
responsibilities and authority, either generally or in specific instances.

     (b) Executive shall report to the Chief Executive Officer or the President
and Chief Operating Officer of the Company.

     (c) During the Employment Period, Executive shall devote his best efforts
and his full business time and attention (except for permitted vacation periods,
reasonable periods of illness or other incapacity, and, provided such activities
do not have more than a DE MINIMIS effect on Executive's performance of his
duties under this Agreement, participation in charitable and civic endeavors and
management of Executive's personal investments and business interests) to the
business and affairs of the Company and the Division. Executive shall perform
his duties and responsibilities to the best of his abilities in a diligent,
trustworthy, businesslike and efficient manner.

     (d) Executive shall perform his duties and responsibilities principally in
the Cleveland, Ohio metropolitan area, and shall not be required to travel
outside that area any more extensively than he has done in the past in the
ordinary course of the business of the Company.


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     3. COMPENSATION AND BENEFITS.

     (a) SALARY. The Company agrees to pay Executive a salary during the
Employment Period, in semi-monthly installments. Executive's initial salary
shall be $265,000 per year. The Compensation Committee of the Board (or, if
there is no such Committee, the Board) shall review Executive's salary from time
to time and may, in its sole discretion, increase it.

     (b) BONUS(ES). Effective January 1, 1999 and for subsequent years,
Executive will be eligible for an annual bonus based on the achievement of
specified Company goals (the "Target Bonus") (as determined by the Compensation
Committee of the Board (or, if there is no such Committee, the Board)). Any
bonus payable pursuant to this subparagraph (b) may, at the discretion of the
Compensation Committee of the Board (or, if there is no such Committee, the
Board), after considering any preference expressed by Executive, be paid in the
form of cash, in a Performance Shares Award related to shares of the Company's
Common Stock or in a combination of both.

     (c) STOCK OPTIONS. The Company has adopted a plan (the "1998 STOCK OPTION
PLAN") pursuant to which options to purchase shares of the Company's Common
Stock, and other equity-based incentive compensation awards, may be granted to
Executive and other officers of the Company. Executive shall be eligible to
receive grants of options and other awards under the 1998 Stock Option Plan, at
the discretion of the Compensation Committee of the Board (or, if there is no
such Committee, the Board). Under the terms of the 1998 Stock Option Plan, the
Compensation Committee of the Board (or, if there is no such Committee, the
Board) has the right to amend the 1998 Stock Option Plan. If, at the time of the
grant of any option pursuant to this paragraph (c), the issuance of shares upon
exercise thereof has not been registered under the Securities Act of 1933, as
amended, it shall be a condition to such grant that Executive execute and
deliver to the Company a certificate confirming that Executive is an accredited
investor (as such term is used in Regulation D under such Act) and including
transfer restrictions and other provisions customary in connection with grants
under such circumstances. Each option to be granted as set forth above shall be
substantially in the form of EXHIBIT 1 attached to this Agreement, except that
it is understood that reference to any then existing registration statement or
related plan information document in EXHIBIT 1, or its equivalent, shall be
included if and only if the same exists at the time of grant and is relevant to
such option.

     (d) EXPENSE REIMBURSEMENT. The Company shall reimburse Executive for all
reasonable expenses incurred by him during the Employment Period in the course
of performing his duties under this Agreement that are consistent with the
Company's policies in effect from time to time with respect to travel,
entertainment and other business expenses, subject to the Company's requirements
applicable generally with respect to reporting and documentation of such
expenses. Executive acknowledges that under the Company's current air travel
reimbursement policy, reimbursement is limited to coach fare (plus Executive's
cost of any upgrade certificates used to upgrade to first class) on travel
within the United States and is limited to business class fare on travel to and
from foreign cities.

     (e) STANDARD EXECUTIVE BENEFITS PACKAGE. In addition to the salary,
bonus(es), stock options and expense reimbursements payable to Executive
pursuant to this paragraph, Executive shall be entitled during the Employment
Period to participate, on the same basis as other executives of the Company, in
the Company's Standard Executive Benefits Package. The Company's "STANDARD
EXECUTIVE BENEFITS PACKAGE" means those benefits (including insurance, vacation,
Company car or car allowance, equity-based benefits, and other benefits) for
which


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substantially all of the executives of the Company are from time to time
generally eligible, as determined from time to time by the Board.

     (f) INDEMNIFICATION. With respect to Executive's acts or failures to act
during the Employment Period in his capacity as a director, officer, employee or
agent of the Company, Executive shall be entitled to indemnification from the
Company, and to liability insurance coverage (if any), on the same basis as
other directors and officers of the Company.

     4. ADJUSTMENTS. Notwithstanding any other provision of this Agreement, it
is expressly understood and agreed that if there is a significant reduction in
the level of the business to which Executive's duties under this Agreement
relate, or if all or any significant part of such business is disposed of by the
Company and/or its subsidiaries or affiliates during the Employment Period but
Executive thereafter remains an employee of the Company, the Compensation
Committee of the Board (or, if there is no such Committee, the Board) may make
adjustments in Executive's duties, responsibility and authority, and in
Executive's compensation, as the Compensation Committee of the Board (or, if
there is no such Committee, the Board) deems appropriate to reflect such
reduction or disposition.

     5. EMPLOYMENT PERIOD.

     (a) Except as hereinafter provided, the Employment Period shall continue
until, and shall end upon, the second anniversary of the date on which the
Employment Period begins.

     (b) On each anniversary of the date on which the Employment Period begins
which precedes Executive's sixty-fifth birthday by more than one year, unless
the Employment Period shall have ended early pursuant to (c) below or either
party shall have given the other party written notice that the extension
provision in this sentence shall no longer apply, the Employment Period shall be
extended for an additional year (unless Executive's sixty-fifth birthday occurs
during such additional year, in which event the Employment Period shall be
extended only until such birthday). In no event shall the Employment Period be
extended beyond Executive's sixty-fifth birthday except by mutual written
agreement of the Company and Executive.

     (c) Notwithstanding (a) and (b) above, the Employment Period shall end
early upon the first to occur of any of the following events:

     (i) Executive's death;

     (ii) Executive's retirement upon or after reaching age 65 ("RETIREMENT");

     (iii) the Company's termination of Executive's employment on account of
Executive's having become unable (as determined by the Board in good faith) to
regularly perform his duties hereunder by reason of illness or incapacity for a
period of more than six (6) consecutive months ("TERMINATION FOR DISABILITY");

     (iv) the Company's termination of Executive's employment for Cause
("TERMINATION FOR CAUSE");


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     (v)  the Company's termination of Executive's employment other than a
          Termination for Disability or a Termination for Cause ("TERMINATION
          WITHOUT CAUSE");

     (vi) Executive's termination of Executive's employment for Good Reason, by
          means of advance written notice to the Company at least thirty (30)
          days prior to the effective date of such termination identifying such
          termination as a Termination by Executive for Good Reason and
          identifying the Good Reason ("TERMINATION BY EXECUTIVE FOR GOOD
          REASON") (it being expressly understood that Executive's giving notice
          that the extension provision in the first sentence of paragraph 5(b)
          hereof shall no longer apply shall not constitute a Termination by
          Executive for Good Reason);

    (vii) Executive's termination of Executive's employment for any reason
          other than Good Reason, by means of advance written notice to the
          Company at least one hundred twenty (120) days prior to the effective
          date of such termination identifying such termination as a Termination
          by Executive with Advance Notice ("TERMINATION BY EXECUTIVE WITH
          ADVANCE NOTICE") (it being expressly understood that Executive's
          giving notice that the extension provision in the first sentence of
          paragraph 5(b) hereof shall no longer apply shall not constitute a
          Termination by Executive with Advance Notice); or

   (viii) the termination of Executive's employment (A) on account of a
          Termination without Cause before the second anniversary of a Change of
          Control, (B) on account of a Termination by Executive for Good Reason
          before the second anniversary of a Change of Control or (C) in
          connection with but prior to a Change of Control and following the
          commencement of any discussion with any third party that (i) requests
          or suggests that Executive's employment be terminated, and (ii)
          ultimately engages in a Change of Control (collectively, "TERMINATION
          FOLLOWING A CHANGE OF CONTROL").
   
      (d) For purposes of this Agreement, "CAUSE" shall mean:

     (i)  the commission by Executive of a felony or a crime involving moral
          turpitude;

     (ii) the commission by Executive of a fraud;

     (iii) the commission by Executive of any act involving dishonesty or
          disloyalty with respect to the Company or any of its subsidiaries or
          affiliates that harms or damages any of them to any extent;

     (iv) conduct by Executive that brings the Company or any of its
          subsidiaries or affiliates into substantial public disgrace or
          disrepute;

     (v)  gross negligence or willful misconduct by Executive with respect to
          the Company or any of its subsidiaries or affiliates;


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     (vi) repudiation of this Agreement by Executive or Executive's abandonment
          of his employment with the Company (it being expressly understood that
          a Termination by Executive for Good Reason or a Termination by
          Executive with Advance Notice shall not constitute such a repudiation
          or abandonment);

    (vii) breach by Executive of any of the agreements in paragraph 8 hereof
          prior to the end of the Employment Period; or

   (viii) any other breach by Executive of this Agreement which is material
          and which is not cured within thirty (30) days after written notice
          thereof to Executive from the Company.

     (e)  For purposes of this Agreement, "GOOD REASON" shall mean:

     (i)  a reduction by the Company in Executive's salary to an amount less
          than "EXECUTIVE'S REFERENCE SALARY" (i.e., Executive's initial salary
          or, in the event the Employment Period has been extended pursuant to
          paragraph 5(b) hereof, Executive's salary on the date on which the
          most recent such extension occurred) or any downward adjustment in
          Executive's Target Bonus; or

     (ii) the Company's giving notice that the extension provision in the first
          sentence of paragraph 5(b) hereof shall no longer apply; or

    (iii) any breach by the Company of this Agreement which is material and
          which is not cured within thirty (30) days after written notice
          thereof to the Company from Executive.

     (f)  For purposes of this Agreement, "CHANGE OF CONTROL" shall mean the
          occurrence of any of the following events during the Employment
          Period:

     (i) The acquisition by any individual, entity or group (within the meaning
of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act")) (a "Person") of beneficial ownership (within the
meaning of Rule 13d-3 promulgated under the Exchange Act) of 40% or more of
either: (A) the then-outstanding shares of common stock of the Company (the
"Company Common Stock") or (B) the combined voting power of the then-outstanding
voting securities of the Company entitled to vote generally in the election of
directors ("Voting Stock"); PROVIDED, HOWEVER, that for purposes of this
subparagraph (i), the following acquisitions shall not constitute a Change of
Control: (A) any acquisition directly from the Company, (B) any acquisition by
the Company, a subsidiary of the Company or the Harris Group, (C) any
acquisition by any employee benefit plan (or related trust) sponsored or
maintained by the Company or any subsidiary of the Company, or (D) any
acquisition by any Person pursuant to a transaction which complies with clauses
(A), (B) and (C) of subparagraph (iii) of this paragraph 5(f); or


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     (ii) Individuals who, as of the date hereof, constitute the Board (the
"Incumbent Board") cease for any reason (other than death or disability) to
constitute at least a majority of the Board; PROVIDED, HOWEVER, that any
individual becoming a director subsequent to the date hereof whose election, or
nomination for election by the Company's shareholders, was approved by a vote of
at least a majority of the directors then comprising the Incumbent Board (either
by a specific vote or by approval of the proxy statement of the Company in which
such person is named as a nominee for director, without objection to such
nomination) shall be considered as though such individual were a member of the
Incumbent Board, but excluding for this purpose, any such individual whose
initial assumption of office occurs as a result of an actual or threatened
election contest (within the meaning of Rule 14a-11 of the Exchange Act) with
respect to the election or removal of directors or other actual or threatened
solicitation of proxies or consents by or on behalf of a Person other than the
Board; or

     (iii) Consummation of a reorganization, merger or consolidation or sale or
other disposition of all or substantially all of the assets of the Company (a
"Business Combination"), in each case, unless, following such Business
Combination, (A) all or substantially all of the individuals and entities who
were the beneficial owners, respectively, of the Company Common Stock and Voting
Stock immediately prior to such Business Combination beneficially own, directly
or indirectly, more than a majority of, respectively, the then-outstanding
shares of common stock and the combined voting power of the then-outstanding
voting securities entitled to vote generally in the election of directors, as
the case may be, of the entity resulting from such Business Combination
(including, without limitation, an entity which as a result of such transaction
owns the Company or all or substantially all of the Company's assets either
directly or through one or more subsidiaries) in substantially the same
proportions relative to each other as their ownership, immediately prior to such
Business Combination, of the Company Common Stock and Voting Stock of the
Company, as the case may be, (B) no Person (excluding any entity resulting from
such Business Combination, the Harris Group or any employee benefit plan (or
related trust) sponsored or maintained by the Company, a subsidiary of the
Company or such entity resulting from such Business Combination) beneficially
owns, directly or indirectly, 40% or more of, respectively, the then-outstanding
shares of common stock of the entity resulting from such Business Combination,
or the combined voting power of the then-outstanding voting securities of such
corporation except to the extent that such ownership existed prior to the
Business Combination and (C) at least a majority of the members of the board of
directors of the corporation resulting from such Business Combination were
members of the Incumbent Board at the time of the execution of the initial
agreement, or of the action of the Board, providing for such Business
Combination; or

     (iv) Approval by the shareholders of the Company of a complete liquidation
or dissolution of the Company.

     (v) For purposes of this paragraph 5(f), the "Harris Group" shall mean
Messrs. Irving B. Harris, Neison Harris, King Harris, William W. Harris and June
H. Barrows, and their respective spouses, descendants and spouses of
descendants, trustees of trusts established for the benefit of such persons
(acting in their capacity as trustees of such trusts), and executors of estates
of such persons (acting in their capacity as executors of such estates), and
each person of which any of the foregoing owns (i) more than fifty percent (50%)
of the voting stock or other voting interests and (ii) stock or other interests


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representing more than fifty percent (50%) of the total value of the stock or
other interests of such person.

     6. POST-EMPLOYMENT PERIOD PAYMENTS.

     (a) If the Employment Period ends on the date on which (without any
extension thereof) it is then scheduled to end pursuant to paragraph 5 hereof,
or if the Employment Period ends early pursuant to paragraph 5 hereof for any
reason, Executive shall cease to have any rights to salary, bonus (if any),
options, expense reimbursements or other benefits other than: (i) any salary
which has accrued but is unpaid, any reimbursable expenses which have been
incurred but are unpaid, and any unexpired vacation days which have accrued
under the Company's vacation policy but are unused, as of the end of the
Employment Period, (ii) any option rights or plan benefits which by their terms
extend beyond termination of Executive's employment (but only to the extent
provided in any option theretofore granted to Executive or any benefit plan in
which Executive has participated as an employee of the Company), (iii) any
benefits to which Executive is entitled under Part 6 of Subtitle B of Title I of
the Employee Retirement Income Security Act of 1974, as amended ("COBRA") and
(iv) any other amount(s) payable pursuant to the succeeding provisions of this
paragraph 6.

     (b) If the Employment Period ends pursuant to paragraph 5 hereof on
Executive's sixty-fifth birthday, or if the Employment Period ends early
pursuant to paragraph 5 hereof on account of Executive's death, Retirement
(provided such Retirement is not a Termination Following a Change of Control) or
Termination for Disability, the Company shall make no further payments to
Executive except as contemplated in (a)(i), (ii) and (iii) above.

     (c) If the Employment Period ends early pursuant to paragraph 5 hereof on
account of Termination for Cause, the Company shall pay Executive an amount
equal to that amount Executive would have received as salary (based on
Executive's salary then in effect) had the Employment Period remained in effect
until the later of the effective date of the Company's termination of
Executive's employment or the date thirty days after the Company's notice to
Executive of such termination. The Company shall make no further payments to
Executive except as contemplated in (a)(i), (ii) and (iii) above.

     (d) If the Employment Period ends early pursuant to paragraph 5 hereof on
account of a Termination without Cause or a Termination by Executive for Good
Reason, and such termination does not constitute a Termination Following a
Change of Control, the Company shall pay to Executive amounts equal to the
amounts Executive would have received as salary (based on Executive's salary
then in effect or, if greater, Executive's Reference Salary) had the Employment
Period remained in effect for a period of twenty-four (24) months after the last
day of the month in which the Employment Period ends (in the event Executive is
entitled during the payment period to any payments under any disability benefit
plan or the like in which Executive has participated as an employee of the
Company, less such payments), payable at the times such amounts would have been
paid; PROVIDED, HOWEVER, that if Executive so chooses, in his sole discretion,
such payment under this subparagraph (d) shall be made in a lump sum. In
addition, the Company shall reimburse Executive (net after taxes on the receipt
of such reimbursement) for any premiums paid by Executive for health insurance
provided to Executive (for Executive and his dependents) by the Company
subsequent to the end of the Employment Period pursuant to the requirements of
COBRA as in effect on the date of this Agreement. The Company shall make no
further payments to Executive except as contemplated in (a)(i), (ii) and (iii)
above. It is expressly understood that the Company's payment


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obligations under this subparagraph (d) shall cease in the event Executive
breaches any of his agreements in paragraph 7 or 8 hereof.

     (e) If the Employment Period ends early pursuant to paragraph 5 hereof on
account of a Termination by Executive with Advance Notice, and such termination
does not constitute a Termination Following a Change of Control, the Company
shall make no further payments to Executive except as contemplated in (a)(i),
(ii) and (iii) above.

   (f)(i) If the Employment Period ends early pursuant to paragraph 5 hereof
          on account of a Termination Following a Change of Control, Executive
          shall be entitled to receive an amount equal to two times the sum of
          (A) Executive's base salary at the time of such termination (or, if
          higher, Executive's Reference Salary) and (B) Executive's Target Bonus
          for the year in which such termination occurs (or, if higher,
          Executive's Target Bonus for the preceding year or the year in which
          the Change of Control occurs), payable at the times such amounts would
          have been paid; PROVIDED, HOWEVER, that if Executive so chooses, in
          his sole discretion, such payment under this subparagraph (f)(i) shall
          be made in a lump sum. In addition, the Company shall reimburse
          Executive (net after taxes on the receipt of such reimbursement) for
          any premiums paid by Executive for health insurance provided to
          Executive (for Executive and his dependents) by the Company subsequent
          to the end of the Employment Period pursuant to the requirements of
          COBRA as in effect on the date of this Agreement.

     (ii) Notwithstanding any provision of this Agreement to the contrary, if
          any amount or benefit to be paid or provided under this Agreement or
          otherwise pursuant to or by reason of any other agreement, policy,
          plan, program or arrangement, including without limitation any bonus,
          stock option, performance share, performance unit, stock appreciation
          right or similar right, or the lapse or termination of any restriction
          on or the vesting or exercisability of any of the foregoing would be
          an "Excess Parachute Payment," within the meaning of Section 280G of
          the Code, or any successor provision thereto, but for the application
          of this sentence, then the payments and benefits to be paid or
          provided under this Agreement shall be reduced to the minimum extent
          necessary (but in no event to less than zero) so that no portion of
          any such payment or benefit, as so reduced, constitutes an Excess
          Parachute Payment; provided, however, that the foregoing reduction
          shall be made only if and to the extent that such reduction would
          result in an increase in the aggregate payment and benefits to be
          provided to Executive, determined on an after-tax basis (taking into
          account the excise tax imposed pursuant to Section 4999 of the Code,
          or any successor provision thereto, any tax imposed by any comparable
          provision of state law, and any applicable federal, state and local
          income taxes). The determination of whether any reduction in such
          payments or benefits to be provided under this Agreement is required
          pursuant to the preceding sentence shall be made at the expense of the
          Company, if requested by the Executive or the Company, by the
          Company's independent accountants. The fact that the Executive's right
          to payments or benefits may be reduced by reason of the limitations
          contained in this paragraph 6(f) shall not of itself limit or
          otherwise affect any other rights of the Executive other than pursuant
          to this Agreement. In the event


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                    that any payment or benefit intended to be provided under
                    this Agreement is required to be reduced pursuant to this
                    paragraph 6(f), the Executive shall be entitled to designate
                    the payments and/or benefits to be so reduced in order to
                    give effect to this paragraph 6(f). The Company shall
                    provide the Executive with all information reasonably
                    requested by the Executive to permit the Executive to make
                    such designation. In the event that the Executive fails to
                    make such designation within 10 business days of the Date of
                    Termination, the Company may effect such reduction in any
                    manner it deems appropriate.

          (g) Without limiting the rights of the Executive at law or in equity,
     if the Company fails to make any payment or provide any benefit required to
     be made or provided hereunder on a timely basis, the Company will pay
     interest on the amount or value thereof at an annualized rate of interest
     equal to the so-called composite "prime rate" as quoted from time to time
     during the relevant period in the Midwest Edition of THE WALL STREET
     JOURNAL. Such interest will be payable as it accrues on demand. Any change
     in such prime rate will be effective on and as of the date of such change.

          (h) Executive shall not be required to mitigate the amount of any
     payment or benefit provided for in this Agreement by seeking other
     employment or otherwise.

          7. CONFIDENTIAL INFORMATION. Executive acknowledges that the
     information, observations and data obtained by him while employed by the
     Company pursuant to this Agreement, as well as those obtained by him while
     employed by the Company or any of its subsidiaries or affiliates or any
     predecessor thereof prior to the date of this Agreement, concerning the
     business or affairs of the Company or any of its subsidiaries or affiliates
     or any predecessor thereof (unless and except to the extent the foregoing
     become generally known to and available for use by the public other than as
     a result of Executive's acts or omissions to act, "CONFIDENTIAL
     INFORMATION") are the property of the Company or such subsidiary or
     affiliate. Therefore, Executive agrees that during the Employment Period
     and for two years thereafter he shall not disclose any Confidential
     Information without the prior written consent of the Chief Executive
     Officer of the Company unless and except to the extent that such disclosure
     is (i) made in the ordinary course of Executive's performance of his duties
     under this Agreement or (ii) required by any subpoena or other legal
     process (in which event Executive will give the Company prompt notice of
     such subpoena or other legal process in order to permit the Company to seek
     appropriate protective orders), and that he shall not use any Confidential
     Information for his own account without the prior written consent of the
     Chief Executive Officer of the Company. Executive shall deliver to the
     Company at the termination of the Employment Period, or at any other time
     the Company may reasonably request, all memoranda, notes, plans, records,
     reports, computer tapes and software and other documents and data (and
     copies thereof) relating to the Confidential Information, or to the work
     product or the business of the Company or any of its subsidiaries or
     affiliates which he may then possess or have under his control.


<PAGE>   10



     8. NON-COMPETE, NON-SOLICITATION.

          (a) Executive acknowledges that in the course of his employment with
     the Company pursuant to this Agreement he will become familiar, and during
     the course of his employment by the Company or any of its subsidiaries or
     affiliates or any predecessor thereof prior to the date of this Agreement
     he has become familiar, with trade secrets and customer lists of and other
     confidential information concerning the Company and its subsidiaries and
     affiliates and predecessors thereof and that his services have been and
     will be of special, unique and extraordinary value to the Company.

          (b) Executive agrees that during the Employment Period and for a
     period of two years after termination of his employment with the Company,
     he shall not in any manner, directly or indirectly, through any person,
     firm or corporation, alone or as a member of a partnership or as an
     officer, director, shareholder, investor or employee of or in any other
     corporation or enterprise or otherwise, engage in or be engaged in, or
     assist any other person, firm, corporation or enterprise in engaging or
     being engaged in, any business then actively being conducted by the Company
     or any of its subsidiaries or affiliates.

          (c) Executive further agrees that during the Employment Period and for
     a period of two years after termination of his employment with the Company,
     he shall not in any manner, directly or indirectly, induce or attempt to
     induce any employee of the Company or of any of its subsidiaries or
     affiliates to quit or abandon his employ.

          (d) Nothing in this paragraph 8 shall prohibit Executive from being:
     (i) a shareholder in a mutual fund or a diversified investment company or
     (ii) a passive owner of not more than 5% of the outstanding equity
     securities of any class of a corporation or other entity which is publicly
     traded, so long as Executive has no active participation in the business of
     such corporation or other entity.

          (e) If, at the time of enforcement of this paragraph, a court holds
     that the restrictions stated herein are unreasonable under circumstances
     then existing, the parties hereto agree that the maximum period, scope or
     geographical area reasonable under such circumstances shall be substituted
     for the stated period, scope or area and that the court shall be allowed to
     revise the restrictions contained herein to cover the maximum period, scope
     and area permitted by law.

          9. ENFORCEMENT. Because Executive's services are unique and because
     Executive has access to Confidential Information and work product, the
     parties hereto agree that the Company would be damaged irreparably in the
     event any of the provisions of paragraph 8 hereof were not performed in
     accordance with their specific terms or were otherwise breached and that
     money damages would be an inadequate remedy for any such non-performance or
     breach. Therefore, the Company or its successors or assigns shall be
     entitled, in addition to other rights and remedies existing in their favor,
     to an injunction or injunctions to prevent any breach or threatened breach
     of any of such provisions and to enforce such provisions specifically
     (without posting a bond or other security).

          10. EXECUTIVE REPRESENTATIONS. Executive represents and warrants to
     the Company that (i) the execution, delivery and performance of this
     Agreement by Executive does not and will not conflict with, breach, violate
     or cause a default under any contract, agreement, instrument, order,
     judgment or decree to which Executive is a party or by which he is bound,
     (ii) Executive is not a party to or bound by any employment agreement,
     noncompete agreement or


<PAGE>   11


confidentiality agreement with any other person or entity, and (iii) upon the
execution and delivery of this Agreement by the Company, this Agreement shall be
the valid and binding obligation of Executive, enforceable in accordance with
its terms.

          11. SURVIVAL. Subject to any limits on applicability contained
     therein, paragraphs 7 and 8 hereof shall survive and continue in full force
     in accordance with their terms notwithstanding any termination of the
     Employment Period.

          12. NOTICES. Any notice provided for in this Agreement shall be in
     writing and shall be either personally delivered, sent by reputable
     overnight carrier or mailed by first class mail, return receipt requested,
     to the recipient at the address below indicated:

                         NOTICES TO EXECUTIVE:
                         ---------------------

                         James D. Atherton
                         3097 Macintosh Drive
                         Westlake, OH  44145

                         NOTICES TO THE COMPANY:
                         -----------------------

                         Mr. Thomas L. Kemp
                         Chief Executive Officer
                         Penton Media, Inc.
                         1100 Superior Avenue
                         Cleveland, OH 44114

or such other address or to the attention of such other person as the recipient
party shall have specified by prior written notice to the sending party. Any
notice under this Agreement will be deemed to have been given when so delivered,
sent or mailed.

          13. SEVERABILITY. Whenever possible, each provision of this Agreement
     shall be interpreted in such manner as to be effective and valid under
     applicable law, but if any provision of this Agreement is held to be
     invalid, illegal or unenforceable in any respect under any applicable law
     or rule in any jurisdiction, such invalidity, illegality or
     unenforceability shall not affect any other provision or any other
     jurisdiction, but this Agreement shall be reformed, construed and enforced
     in such jurisdiction as if such invalid, illegal or unenforceable provision
     had never been contained herein.

          14. PAYMENT OF CERTAIN COSTS AND EXPENSES.

          (a) PREVAILING PARTY'S LITIGATION EXPENSES. In the event of litigation
     between the Company and Executive related to this Agreement, the
     non-prevailing party shall reimburse the prevailing party for any costs and
     expenses (including without limitation attorneys' fees) reasonably incurred
     by the prevailing party in connection therewith.

          (b) CHANGE OF CONTROL OF THE COMPANY. Without limiting the generality
     of (a) above, in the event that there is a Change of Control of the
     Company, if it should appear to Executive that the Company has failed to
     comply with any of its obligations under this Agreement or in the event
     that the Company or any other person takes or threatens to take any action
     to declare this Agreement void or unenforceable, or institutes any
     litigation or other action or proceeding


<PAGE>   12



designed to deny, or to recover from, Executive the benefits provided or
intended to be provided to Executive hereunder, the Company irrevocably
authorizes Executive from time to time to retain counsel of Executive's choice,
at the expense of the Company as hereafter provided, to advise and represent
Executive in connection with any such interpretation, enforcement or defense,
including without limitation the initiation or defense of any litigation or
other legal action, whether by or against the Company or any Director, officer,
shareholder or other person affiliated with the Company, in any jurisdiction.
Notwithstanding any existing or prior attorney-client relationship between the
Company and such counsel, the Company irrevocably consents to Executive's
entering into an attorney-client relationship with such counsel, and in that
connection the Company and Executive agree that a confidential relationship will
exist between Executive and such counsel. Without respect to whether Executive
prevails, in whole or in part, in connection with any of the foregoing, the
Company will pay and be solely financially responsible for any and all
attorneys' and related fees and expenses incurred by Executive in connection
with any of the foregoing.

     (c) SOURCE OF PAYMENTS. Except as otherwise specified herein, in the event
a Change of Control occurs, any payments to Executive pursuant to this Agreement
and the performance of the Company's obligations hereunder shall be secured by
amounts deposited or to be deposited in a trust established by the Company for
the benefit of Executive (and, at the Company's option, for the benefit of other
executives of the Company who are entitled to payments similar to those provided
in this Agreement) (the "Trust"). The Company shall transfer to such Trust
assets from which all or a portion of the payments provided under this Agreement
are to be paid, provided that such assets of the Trust shall at all times be
subject to the claims of general unsecured creditors of the Company and that
neither Executive nor any other person entitled to payments through the Trust
shall at any time have a prior claim to such assets. Any payments to Executive
under this Agreement that are not paid through the Trust shall be paid from the
Company's general assets, and Executive shall have the status of a general
unsecured creditor with respect to the Company's obligations to make payments
under this Agreement.

     15. COMPLETE AGREEMENT. This Agreement embodies the complete agreement and
understanding between the parties with respect to the subject matter hereof and
effective as of its date supersedes and preempts any prior understandings,
agreements or representations by or between the parties, written or oral, which
may have related to the subject matter hereof in any way.

     16. COUNTERPARTS. This Agreement may be executed in separate counterparts,
each of which shall be deemed to be an original and both of which taken together
shall constitute one and the same agreement.

     17. SUCCESSORS AND ASSIGNS. This Agreement shall bind and inure to the
benefit of and be enforceable by Executive, the Company and their respective
heirs, executors, personal representatives, successors and assigns, except that
neither party may assign any of his or its rights or delegate any of his or its
obligations hereunder without the prior written consent of the other party.
Executive hereby consents to the assignment by the Company of all of its rights
and obligations hereunder to any successor to the Company by merger or
consolidation or purchase of all or substantially all of the Company's assets,
provided such transferee or successor assumes the liabilities of the Company
hereunder.

     18. CHOICE OF LAW. This Agreement shall be governed by the internal law,
and not the laws of conflicts, of the State of Ohio.


<PAGE>   13


     19. AMENDMENT AND WAIVER. The provisions of this Agreement may be amended
or waived only with the prior written consent of the Company and Executive, and
no course of conduct or failure or delay in enforcing the provisions of this
Agreement shall affect the validity, binding effect or enforceability of this
Agreement.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date written below.

                                             PENTON MEDIA, INC.

Date:             February 5, 1999           By   /s/ THOMAS L. KEMP
                                               ---------------------
                                                  Thomas L. Kemp
                                                  Chief Executive Officer

Date:             February 12, 1999              /s/ JAMES D. ATHERTON
                                               ---------------------
                                                  James D. Atherton