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                                                                    Exhibit 10.9

                               PENTON MEDIA, INC.
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN
            (As Amended and Restated Effective as of January 1, 2000)

                                    SECTION 1

                                  Introduction

1.1 The Plan and Its Effective Date. This Penton Media, Inc. Supplemental
Executive Retirement Plan (As Amended and Restated Effective as of January 1,
2000, 1999) (the "Plan") was first established by Penton Media, Inc. (the
"Company") effective August 7, 1998 (the "Effective Date").

1.2 Purpose. The Company maintains the Penton Media, Inc. Retirement Plan (as
the same may hereafter be amended, the "Retirement Plan"), which is intended to
meet the requirements of a "qualified plan" under the Internal Revenue Code of
1986, as amended (the "Code"). For purposes of this Plan, the Retirement Plan
shall be deemed to include the Pittway Corporation Retirement Plan (the "Pittway
Plan"), to which the Retirement Plan is a successor. While the Code places
limitations on the maximum benefits which may be paid from a qualified plan and
the maximum amount of an employee's compensation that may be taken into account
for determining benefits payable under a qualified plan, the Employee Retirement
Income Security Act of 1974, as amended ("ERISA"), permits the payment under an
"unfunded plan" of benefits which may not be paid under a qualified plan because
of such limitations. The purpose of the Plan is to provide certain key employees
of the Company and its subsidiaries with certain benefits which may not be
provided under the Retirement Plan because of the maximum compensation
limitation of the Code.

                                    SECTION 2

                            Eligibility and Benefits

2.1 Eligibility. Each key employee of the Company or a subsidiary of the Company
who participates in the Retirement Plan and who is designated by the Committee
(as defined in section 3.1 below) shall participate in the Plan (a
"Participant"), subject to the conditions and limitations of the Plan.

2.2 Accrued Benefit.

         (a)      Subject to subsections (b) and (c) of this Section, for each
                  full calendar year and any final fraction of a calendar year
                  of a Participant's duration of employment with the Company
                  and, prior to the Effective Date, with the Pittway Companies
                  (as such term is defined in the Pittway Plan) (the "Employment
                  Period"), the Participant shall accrue a benefit under the
                  Plan equal to the benefit that he would



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                  have received under the Retirement Plan but for the Maximum
                  Dollar Limitation and the Maximum Benefit Limitation (as
                  defined below) and if the definition of "earnings" under the
                  Retirement Plan was as set forth in section 2.3 below, reduced
                  by the benefit that the Participant actually accrues under the
                  Retirement Plan. For purposes of the Plan, (i) "Maximum Dollar
                  Limitation" means, for any year or fraction of a year, the
                  greater of $150,000 or the dollar amount of any higher maximum
                  limitation on annual compensation taken into account under a
                  qualified plan for such year or fraction of a year determined
                  by the Secretary of Treasury or his delegate or by law under
                  section 401(a) (17) of the Code; it being understood that
                  annual compensation for purposes of such limitation is
                  computed differently from Earnings for purposes of the Plan;
                  and (ii) "Maximum Benefit Limitation" means the limitation
                  imposed by Section 415 of the Code on benefits payable under
                  the Retirement Plan. A Participant's accrued benefits under
                  the Plan shall be referred to hereinafter as the Participant's
                  "Supplemental Retirement Benefits."

         (b)      The Committee may specify as to any Participant a date
                  subsequent to the commencement of the Participant's employment
                  with the Company and the Pittway Companies as the date as of
                  which the Participant shall begin to accrue a benefit under
                  the Plan, and only periods after such date shall be treated as
                  employment with the Company and the Pittway Companies for
                  purposes of subsection (a) of this Section.

         (c)      Notwithstanding anything herein to the contrary, any
                  Participant who ceases to be an employee of the Company
                  without a vested benefit under the Retirement Plan shall not
                  be eligible to receive any benefit under the Plan.

2.3 Earnings. For purposes of the Plan, a Participant's "Earnings" for any year
or fraction means his total, regular cash compensation paid for such year or
fraction for services rendered to any Penton Company (as such term is defined in
the Retirement Plan) or, prior to the Effective Date, to the Pittway Companies
(as such term is defined in the Pittway Plan) during such year or fraction,
consisting solely of his salary and his annual discretionary cash bonus, if any,
for such year. The Committee may specify as to any Participant or as to all
Participants a maximum dollar amount of Earnings that may be taken into account
under the Plan. It is expressly understood that a Participant's Earnings do not
include any other compensation, including, without limitation, any of the
following:

         (a)      Long-term incentive compensation;

         (b)      Unused vacation pay;

         (c)      Special cash bonuses;

         (d)      Any income realized for Federal income tax purposes as a
                  result of the grant or exercise of an option or options to
                  acquire shares of common stock of a Pittway Company or the
                  Company, the receipt or exercise of any stock appreciation
                  right


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                  or payment, or the disposition of shares acquired by the
                  exercise of such an option or right;

         (e)      Any noncash compensation, including any amounts contributed by
                  the Participant's employer(s) for his benefit under the
                  Retirement Plan or any other retirement or benefit plan,
                  arrangement, or policy maintained by his employer(s);

         (f)      Any reimbursements for medical, dental or travel expenses,
                  automobile allowances, relocation allowances, educational
                  assistance allowances, awards and other special allowances;

         (g)      Any income realized for Federal income tax purpose as a result
                  of (i) group life insurance, (ii) the personal use of an
                  employer-owned automobile, or (iii) the transfer of restricted
                  shares of stock or restricted property of a Pittway Company or
                  the Company, or the removal of any such restrictions;

         (h)      Any severance pay paid as a result of the Participant's
                  termination of employment (it being expressly understood that
                  any amount(s) taken into account pursuant to the final
                  sentence of section 2.8 below shall not be deemed severance
                  pay for purposes hereof); or

         (i)      Any compensation paid or payable to the Participant, or to any
                  governmental body or agency on account of the Participant,
                  under the terms of any state, Federal or foreign law requiring
                  the payment of such compensation because of the Participant's
                  voluntary or involuntary termination of employment with the
                  Company.

Notwithstanding the foregoing, a Participant's Earnings do include (i) any
salary reduction amount elected by the Participant and credited to a cafeteria
plan (as defined in section 125(c) of the Code) or a qualified cash or deferred
arrangement (as defined in section 401(k) of the Code) and (ii) the initial
value ascribed to any performance shares, deferred shares, restricted shares or
similar award the Participant elects to receive in lieu of a portion of his
annual discretionary cash bonus.

2.4 Payment of Benefits. Subject to the conditions and limitations of the Plan,
upon a Participant's attainment of age 65 years, he shall be entitled to a
monthly benefit payable for his life commencing upon his attainment of age 65
years (or upon his retirement, if later) in an amount equal to one-twelfth
(1/12) of the sum of the Participant's accrued Supplemental Retirement Benefits.
A Participant's Supplemental Retirement Benefits shall be paid to him in the
form described below that applies to the Participant; provided, however, that in
lieu of payment in the normal form described below, the Participant may
irrevocably elect, within thirty (30) days after his commencement of
participation in the Plan, to receive his Supplemental Retirement Benefits in a
single lump sum as soon as practicable after his attainment of age 65 years. A
Participant's "Supplemental Retirement Benefit Commencement Date" means the date
as of which the initial payment (or, in the case of a single lump sum, full
payment) of the Supplemental Retirement Benefits to which the Participant is
entitled is payable. Subject to the


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conditions and limitations of the Plan, a Participant's Supplemental Retirement
Benefit Commencement Date shall normally be the first day of the calendar month
coincident with or next following the Participant's attainment of age 65 years.
Notwithstanding the immediately preceding sentence, if a Participant's
Employment Period terminates prior to his attainment of age 65 years and he is
eligible, and elects, to receive early retirement benefits under the Retirement
Plan, and if the Participant requests a Supplemental Retirement Benefit
Commencement Date prior to his attainment of age 65 years, then with (but only
with) the consent of the Committee, the Participant's Supplemental Retirement
Benefit Commencement Date shall be such earlier date, if any, selected by the
Committee. Supplemental Retirement Benefits that are paid in a lump sum, or
commence, before the Participant's attainment of age 65 years, if any, shall be
subject to actuarial reduction in accordance with section 2.5 below.

         (a)      Life Annuity. If a Participant does not have a Spouse (as
                  defined in section 2.7 below) on his Supplemental Retirement
                  Benefit Commencement Date, and if he has not elected pursuant
                  to the preceding provisions of this section 2.4 to receive his
                  Supplemental Retirement Benefits in a single lump sum, payment
                  of his Supplemental Retirement Benefits shall be during his
                  lifetime on a life annuity basis.

         (b)      Joint and Survivor Annuity. If a Participant has a Spouse on
                  his Supplemental Retirement Benefit Commencement Date, payment
                  of his Supplemental Retirement Benefits shall be in the form
                  of a joint and 50 percent survivor annuity unless the
                  Participant has theretofore elected pursuant to the preceding
                  provisions of this section 2.4 to have his benefits provided
                  in a single lump sum.

                  Such joint and 50 percent survivor annuity shall consist of a
                  reduced monthly benefit continuing during the Participant's
                  lifetime, and if such Spouse is living at the time of the
                  Participant's death, payment of 50 percent of such monthly
                  benefit shall be made to such Spouse until such Spouse's death
                  occurs. The amount of the Participant's and such Spouse's
                  benefits under this subsection shall be calculated so that it
                  is the actuarial equivalent of the Supplemental Retirement
                  Benefits to which the Participant would otherwise be entitled
                  under the Plan. If such Spouse predeceases the Participant, or
                  if the Participant and such Spouse cease to be married after
                  the Participant's Supplemental Retirement Benefit Commencement
                  Date, there shall be no adjustment to the Participant's
                  monthly payments and no Supplemental Retirement Benefits shall
                  be payable to any person after the Participant's death.

2.5 Actuarial Equivalent. A benefit shall be actuarially equivalent to another
benefit if the actuarial reserve required to provide such benefit is equal to
the actuarial reserve required to provide such other benefit, computed on the
basis of the same actuarial assumptions, interest rates, tables, methods and
procedures, including reduction factors for commencement of payments prior to
attainment of age 65 years, that are used for purposes of the Retirement Plan as
in effect on the applicable date that a benefit payment amount is determined.


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2.6 Pre-Retirement Surviving Spouse Benefit. If a Participant dies prior to his
Supplemental Retirement Benefit Commencement Date, no Supplemental Retirement
Benefits under the Plan shall be paid or payable with respect to the
Participant; provided, however, that if the Participant has a Spouse at the time
of his death, such Spouse shall be entitled to receive a monthly benefit for
such Spouse's lifetime equal to 50 percent of the amount of monthly benefit that
would have been payable to the Participant in the form of a joint and 50 percent
survivor annuity if he had terminated employment as of the date of his death
with entitlement to Supplemental Retirement Benefits under the Plan and the
Committee had permitted his Supplemental Retirement Benefit Commencement Date to
occur on the first day of the calendar month coincident with or next following
the date of his death, taking into account actuarial reduction for commencement
prior to the Participant's attainment of age 65 years. The first payment to the
Spouse shall be made as of the first day of the calendar month coincident with
or next following the date of the Participant's death and the final payment
shall be made as of the first day of the calendar month during which the
Spouse's death occurs. If, prior to the Participant's death, the Participant had
elected pursuant to section 2.4 above to receive his Supplemental Retirement
Benefits in a single lump sum, in lieu of the monthly payments described above,
such Spouse shall be entitled to receive a single lump sum equal to 50 percent
of the lump sum value of the Participant's Supplemental Retirement Benefits as
of the date of his death, taking into account actuarial factors for payment
prior to the Participant's attainment of age 65 years. Such lump sum payment
shall be made to such Spouse as soon as practicable following the Participant's
death.

2.7 Spouse. For purposes of the Plan, a person will be considered the "Spouse"
of a Participant as of any date if and only if such person and the Participant
have been married in a religious or civil ceremony recognized under the laws of
the nation or state where the marriage was contracted and the marriage remains
legally effective. Any person who is not, or who has ceased to be, a
Participant's Spouse on the Participant's Supplemental Retirement Benefit
Commencement Date (or, in the event of the Participant's death prior to his
Supplemental Retirement Benefit Commencement Date, the date of his death) shall
not be considered the Participant's Spouse for purposes of the Plan.

2.8 Forfeiture; Early Termination of Employment Period. If the Participant's
Employment Period ends on account of a Termination for Cause (as defined below),
the Participant shall forfeit all of his Supplemental Retirement Benefits, if
any, under the Plan, no benefit under the Plan shall thereafter be payable to or
with respect to the Participant or his Spouse, and any benefit under the Plan
theretofore paid to or with respect to the Participant or his Spouse must be
repaid to the Company by the Participant or his Spouse promptly upon demand.

For purposes of the Plan, "Termination for Cause" shall mean termination of a
Participant's employment because of:

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

                  (b)      the commission by the Participant of a fraud;


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                  (c)      the commission by the Participant 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;

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

                  (e)      gross negligence or willful misconduct by the
                           Participant with respect to the Company or any of its
                           subsidiaries or affiliates.

2.9 Funding. The Plan is intended to be non-qualified for purposes of the Code
and unfunded for purposes of the Code and ERISA. Benefits payable under the Plan
to a Participant and/or his Spouse, as the case may be, shall be paid directly
by the Company. The Company shall not be required to segregate on its books or
otherwise any amount to be used for payment of Supplemental Retirement Benefits
under the Plan. Each Participant and Spouse is solely an unsecured creditor of
the Company with respect to any benefit payable with respect to a Participant
hereunder.

                                    SECTION 3

                               General Provisions

3.1 Committee. The Plan shall be administered by the administrative committee of
the Retirement Plan (the "Committee"). The Committee shall have, to the extent
appropriate, the same powers, rights, duties and obligations with respect to the
Plan as it has with respect to the Retirement Plan. Each determination provided
for in the Plan shall be made by the Committee under such procedure as may from
time to time be prescribed by the Committee and shall be made in the absolute
discretion of the Committee. Any determination so made shall be conclusive.

3.2 Employment Rights. Neither the establishment of, nor participation in, the
Plan shall be construed to give any Participant the right to be retained in the
service of the Penton Companies or to any benefits not specifically provided by
the Plan.

3.3 Taxes and Withholding. Each Participant (or his Spouse, as applicable) shall
be responsible for any taxes imposed on him (or his Spouse) by reason of the
establishment of, or his participation in, the Plan, including, without
limitation, any Federal, state and/or local income or employment taxes imposed
on benefits or potential benefits under the Plan (or on the value thereof)
("Taxes") in advance of the Participant's receipt of such benefits or potential
benefits. The Company or a subsidiary of the Company may deduct any Taxes from
payroll or other payments due the Participant or his Spouse. The Committee shall
deduct from all payments under the Plan any Taxes required to be withheld. In
the event that such deductions and/or withholdings are not sufficient to pay the
Taxes, the Participant (or his Spouse) shall promptly remit the deficit to the
Company upon its request.


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3.4 Interests Not Transferable. Except as to withholding of any Taxes, the
interests of Participants and their Spouses under the Plan are not subject to
the claims of their creditors and may not be voluntarily or involuntarily
transferred, assigned, alienated or encumbered. No Participant shall have any
right to any benefit payments hereunder prior to his termination of employment
with the Penton Companies.

3.5 Payment with Respect to Incapacitated Participants or Beneficiaries. If any
person entitled to benefits under the Plan is under a legal disability or in the
Committee's opinion is incapacitated in any way so as to be unable to manage his
financial affairs, the Committee may direct the payment of such benefit to such
person's legal representative or to a relative or friend of such person for such
person's benefit, or the Committee may direct the application of such benefits
for the benefit of such person in any manner which the Committee may select that
is consistent with the Plan. Any payments made in accordance with the foregoing
provisions of this section shall be a full and complete discharge of any
liability for such payments.

3.6 Limitation of Liability. To the extent permitted by law, no person
(including the Company, any subsidiary of the Company, the Board of Directors of
the Company (the "Board"), the board of directors of any subsidiary of the
Company, the Committee, any present or former member of the Board or of the
board of directors of any subsidiary of the Company or of the Committee, and any
present or former officer of the Company or of any subsidiary of the Company)
shall be personally liable for any act done or omitted to be done in good faith
in the administration of the Plan.

3.7 Controlling Law. The Plan shall be construed in accordance with the
provisions of ERISA and other Federal laws, to the extent such provisions are
applicable to the Plan. To the extent not inconsistent therewith, the Plan shall
be construed in accordance with the laws of the State of Ohio.

3.8 Gender and Number. Where the context admits, words in the masculine gender
shall include the feminine and neuter genders, the plural shall include the
singular and the singular shall include the plural.

3.9 Action by the Company. Any action required of or permitted by the Company
under the Plan, including action by the Company to amend the Plan, shall be by
resolution of the Board or by a duly authorized committee of the Board or by a
person or persons authorized by resolution of the Board or such committee. The
procedure for amending the Plan is that the Plan shall be amended by the Company
taking appropriate corporate action to effectuate any amendment considered by it
to be advisable to be made. Appropriate corporate action includes action by
resolution of the Board, by a committee authorized by the Board, or by a person
or persons authorized by the Board or such committee, as provided above.

3.10 Successor to the Company. The term "Company" as used in the Plan shall
include any successor to the Company by reason of merger, consolidation, the
purchase of all or substantially all of the Company's assets or otherwise.


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3.11 Miscellaneous. The Plan shall be binding upon and inure to the benefit of
the parties, their legal representatives, successors and assigns, and all
persons entitled to benefits hereunder. Any notice given in connection with the
Plan shall be in writing and shall be delivered in person or by registered mail,
return receipt requested. Any notice given by registered mail shall be deemed to
have been given upon the date of delivery indicated on the registered mail
return receipt, if correctly addressed.

                                    SECTION 4

                            Amendment and Termination

While the Company expects to continue the Plan, it must necessarily reserve, and
hereby does reserve, the right, either in general or as to one or more
particular Participants, to amend the Plan from time to time or to terminate the
Plan at any time; provided that no amendment of the Plan with respect to a
Participant that reduces or eliminates any benefits such Participant has accrued
as of the effective date of such amendment shall be effective unless such
Participant consents to such amendment.


         IN WITNESS WHEREOF, this Plan has been executed on behalf of the
Company by its duly authorized officers as of the day and year first above
written.

                                                   PENTON MEDIA, INC.


                                                   By:   ______________________

                                                   Its:  ______________________

                                                   Date: ______________________


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