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                                                                   Exhibit 10(k)

10(k) Employment Agreement with Mark J. Plush

                              EMPLOYMENT AGREEMENT

         EMPLOYMENT AGREEMENT dated this 7th day of April 1994 between Keithley
Instruments, Inc., an Ohio corporation, (hereinafter called the "Company"), and
Mark J. Plush (hereinafter called the "Employee").

         WHEREAS, the "Company" considers the establishment and maintenance of
sound and vital management to be essential to protecting and enhancing the best
interest of the Company and its shareholders; and

         WHEREAS, the Company wishes to assure itself of the Employee's
full-time employment during the period specified herein; and

         WHEREAS, the Employee is prepared to enter into an employment agreement
with the Company and to give the Company the assurances it desires;

         NOW, THEREFORE, in consideration of the foregoing premises and of the
mutual agreements herein set forth, the parties hereto have agreed and do hereby
mutually agree as follows:

I)   TERM OF AGREEMENT

     A)   GENERAL. The term of this Agreement shall commence on the date first
          above written, and shall continue for three years, through and
          including April 7, 1997, unless sooner terminated pursuant to Section
          VI or XII hereinbelow. After the original three year term, the
          Agreement is renewable automatically for successive one year terms
          unless either party gives the other party written notice of
          non-renewal at least thirty (30) days before the end of the term of
          the Agreement.
     B)   CHANGE IN CONTROL. In the event that Joseph P. Keithley & Trusts of
          which he is a Partner ceases to have more than fifty percent (50%)
          voting power of the Company's voting stock ("Change of Control")
          during the term of this Agreement, as set forth above, this Agreement
          will continue for the balance of said term. If the balance of said
          term is less than eighteen months, the term of this Agreement shall be
          extended so that the term shall not end prior to eighteen months
          following the date of the Change of Control.

II)  RESPONSIBILITY

     It is agreed that the Employee is hereby employed by the Company with
     responsibility to perform such duties, consistent with his position, as
     shall be assigned to him by the Chief Executive Officer or Board of
     Directors of the Company.

III) ACCOUNTABILITY

     It is agreed that in exercising his responsibilities, the Employee will be
     accountable to the Company's Board of Directors and its Chief Executive
     Officer. The employee agrees to: (i) devote his business time and efforts
     full-time to the affairs of the Company and its affiliates, and (ii) use
     his best efforts to promote the interests of the Company and its
     affiliates.


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IV)  REMUNERATION

     A)   BASE SALARY. The Employee will be employed during the term of this
          Agreement at an annual base salary of not less than $109,800, paid on
          a monthly basis. This base salary maybe increased, but not decreased
          without the Employee's consent, at the discretion of the Compensation
          Committee of the Board of Directors of the Company.

     B)   ADDITIONAL COMPENSATION. The Employee shall be eligible to participate
          in incentive, stock option, profit-sharing, annual cash bonus,
          deferred compensation and similar plans maintained by the Company for
          the benefit of its executives.

V)   OTHER EMPLOYEE FRINGE BENEFITS

     The Employee shall be included to the extent eligible thereunder (at the
     expense of the Company, if provided at Company expense for other executives
     of the Company with a comparable level of responsibility) under any and all
     existing plans or arrangements (and any plans or arrangements which may be
     adopted) providing benefits for its employees, including but not limited to
     group life insurance, hospitalization, medical, pension, automobile,
     financial services and any and all other similar or comparable benefits as
     may be in effect for other executives of the Company with a comparable
     level of responsibility from time to time during the term of this
     Agreement. Additional or improved fringe benefits are to be calculated for
     and awarded to the Employee in at least as beneficial a manner as they are
     calculated for and awarded to such other executive.

     Nothing in this Agreement shall adversely affect the rights of the Employee
     or his beneficiaries under the present of any future retirement,
     profit-sharing, insurance, or other fringe benefit or compensation plans or
     arrangements which the Company now has or may adopt for its employees, and
     no rights or the Employee thereunder shall be forfeited by any action set
     forth in this Agreement unless so provided in such plans or arrangements.

VI)  TERMINATION OF EMPLOYMENT
     A)   DEATH. If the Employee shall die during the term of this Agreement,
          the duties of the Company and the Employee, one to the other, under
          this Agreement shall terminate as of the date of the Employee's death.
          Notwithstanding the sentence immediately preceding, the death of the
          Employee shall not adversely affect the rights of this beneficiaries
          to any benefits under the Company's employee benefit plans or
          arrangements in which he may be a participant, in accordance with the
          terms thereof, including but not limited to those referred to in
          Section VI, F hereof.
     B)   DISABILITY. If the Employee shall become disabled for purposes of the
          Company's long-term disability program during the term of this
          Agreement the duties of the Company and the Employee, one to the
          other, under this Agreement shall terminate as of the date the
          Employee is determined to be disabled. Notwithstanding the sentence
          immediately preceding, the disability of the Employee shall not
          adversely affect his rights to any benefits under the Company's
          employee benefit plans or arrangements in which he may be a
          participant, in accordance with the provisions thereof, including but
          not limited to those referred to in Section VI, F hereof.
     C)   RESIGNATION. If the Employee voluntarily leaves the employ of the
          Company during the term of this Agreement for any reason, the duties
          of the Company and the Employee, one to the other, under this
          Agreement shall terminate as of the date of the Employee's termination
          of employment. Notwithstanding the sentence immediately preceding,
          such voluntary termination of employment by the Employee shall not
          adversely affect his rights to any benefits under the Company's
          employee benefit plans or arrangements in

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          which he may be a participant, in accordance with the provisions
          thereof, including but not limited to those referred to in Section VI,
          F hereof.

     D)   TERMINATION BY COMPANY. The Company may terminate the Employee's
          employment at any time, without cause, subject to providing the
          benefits hereinafter specified in accordance with the terms hereof.
          The Company may terminate the Employee's employment at any time "For
          Cause". In the event the Company shall terminate the Employee's
          employment For Cause, the duties of the Company and the Employee, one
          to the other, under this Agreement shall terminate as of the date of
          the Employee's termination of employment. Notwithstanding the sentence
          immediately preceding, such termination of employment of the Employee
          by the Company For Cause shall not adversely affect his rights to any
          benefits under the Company's employee benefit plans or arrangements in
          which he may be a participant, in accordance with the provisions
          thereof, including but not limited to those referred to in Section VI,
          F hereof.

As used herein the words "For Cause" shall be deemed to mean and include (i) the
Employee's conviction of either a felony involving moral turpitude or any crime
in connection with his employment by the Company which causes the Company or any
affiliated company a substantial detriment; or (ii) the Employee's refusal to
submit to a medical examination if directed to do so by the Board to determine
whether the Employee is disabled under subsection VI(B) hereof; or (iii) the
Employee's willful failure to take actions permitted by law and necessary to
implement policies of the Board which the Board has communicated to him in
writing, provided that minutes of a Board meeting attended in its entirety by
the Employee shall be deemed communicated to the Employee; or (iv) the
Employee's continued failure to perform his duties as an executive officer of
the Company as set forth in the attached job description (provided that the
Employee's competence in such performance shall be irrelevant); or (v) any
condition which either resulted from the Employee's habitual drunkenness or
addiction to narcotics, or resulted from any intentionally self-inflicted
injury; or (vi) acting in breach or contravention of any material obligation,
covenant or agreement of the Employee contained in this Agreement, expressly
including without limitation, the non-competition and non-solicitation covenants
set forth in Section VIII hereof or the provision of the "Employee Agreement" or
any similar agreement regarding confidentiality.

     E)   NOTICE OF TERMINATION. Any termination of the Employee's employment by
          the Company or by the Employee shall be communicated by written Notice
          of Termination to the other party hereto which notice shall set forth
          the effective date of such termination which shall not be earlier than
          the date of mailing, or delivery by other means, of the notice.

     F)   CONTINUATION OF EMPLOYEE BENEFITS. The death, disability or
          termination of employment of the Employee, whether or not voluntary
          and whether or not For Cause shall not result in the loss by the
          Employee or his beneficiaries of any benefits under any life
          insurance, death benefit, pension, profit sharing, stock option,
          medical, deferred compensation or other employee benefit plan or
          arrangement except as provided for in such plan or arrangement.

VII) COMPENSATION UPON INVOLUNTARY TERMINATION OTHER THAN FOR CAUSE

     If the Employee's employment with the Company shall be terminated, during
     the term of this Agreement, by the Company other than For Cause, then the
     Employee shall be entitled to the benefits provided below:

     i)     the Company shall pay the Employee, on a monthly basis, his full
          monthly base salary determined as of the date of his termination of
          employment, for six

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          months following his termination of employment, or one month following
          his termination of employment for each full year of his service with
          the Company, whichever is greater, up to a maximum of eighteen (18)
          months;

     ii)    full participation in the annual Extra Compensation Plan if his
          termination of employment is on or subsequent to June 30 of the
          respective fiscal year;

     iii)   full participation in any performance award if the performance
          measuring period ends within six months follow his termination of
          employment;

     iv)    the choice of exercising all vested stock options up to thirty days
          after his termination of employment, provided this provision shall not
          extend the term of his options beyond their terms as initially
          granted, and the Company agrees to request the Compensation Committee
          of its Board of Directors to permit such exercise pursuant to Section
          6(g) of the Keithley Instruments, Inc. 1984 Stock Option Plan or the
          comparable provision of any future plan;

     v)     the Employee shall be deemed to have vested in his stock, if any,
          acquired under the Company's restricted stock plan at a rate of 20%
          per year of service subsequent to the date of sale of such stock to
          the Employee;

     vi)    the Company shall maintain in full force and effect, following his
          termination of the Employee's employment for six months following such
          termination of employment for each full year of his service with the
          Company, whichever is greater, up to a maximum of eighteen (18)
          months, all employee fringe benefit plans and arrangement in which he
          was entitled to participate immediately prior to the date of the
          Notice of Termination, provided that if such continued coverage would
          jeopardize the tax qualified status of such plan or arrangement with
          respect to any other employee or the Company the Company may elect to
          provide the said benefit on an individual basis or provide cash
          compensation equivalent to the benefit which otherwise would have been
          provided so that the Employee shall suffer no financial loss
          whatsoever due to such substitution;

     vii)   in addition to the retirement benefits to which the Employee is
          entitled under the Company's Employees' Pension Plan, as amended from
          time to time (the "Pension Plan"), the Company shall pay a
          supplemental retirement benefit hereunder, which benefit (except as
          provided below) shall be determined in accordance with, and payable in
          the same form and at the same times provided in, the Pension Plan.
          Such benefit shall equals (a) minus (b) below where:

          (a)  equals the benefit to which the Employee would be entitled under
               the Pension Plan if:

               I.     he were fully vested;

               II.    his "compensation", as that word is defined in the Pension
                    Plan, were, at all times while he was a participant in said
                    Pension Plan, equal to the annual amount of such
                    compensation for that Company fiscal year from among the
                    final three (3) Company fiscal years ending prior to his
                    termination of employment for which said compensation was
                    the highest;

               III.   his "1977 monthly compensation", "1983 monthly 
                    compensation" and any similar updated monthly compensation
                    were calculated by dividing his "compensation", as defined
                    in Section VII, (vii), (a) II. above, by twelve (12); and

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               IV.    he was credited with his actual years of "credited 
                    service" as determined under the Pension Plan; and

          b)   equals the Employee's actual benefit payable under the Pension
               Plan; and

     viii)   reimbursement of fees for outplacement services actually used to 
          the extent approved by the Chief Executive Officer in his sole
          discretion, but not in excess of $10,000.

         Nothing in this Agreement shall be construed as amending any
         compensation or fringe benefit plan or arrangement of the Company. All
         rights of the Employee under any such plan or arrangement upon his
         termination of employment must be determined under the terms of such
         plans or arrangements at the time of the Employee's termination of
         employment.

VIII) COVENANT NOT TO COMPETE
      -----------------------
     The Employee agrees that during his employment with the Company, and after
     his termination of employment for as long as payments hereunder are made by
     the Company, the Employee shall remain in full compliance with the
     following conditions:

     i)     He must not accept employment either directly or indirectly, with 
     any competitor of the Company.

     ii)    He must not allow the use of his name by or in any competitive
          business.

     iii)   He must keep himself at all times reasonably available for
          consultation by the officers and directors of the Company; provided
          that no such consultation shall be required after the Employee attains
          age sixty-five (65). In the event he is called upon to render any such
          substantial consulting services, he shall receive additional
          compensation in a reasonable amount, and any travel or other expenses
          which may be required in connection with such services shall be paid
          by the Company.

         The Company shall make payments under this Agreement only so long as
         the Employee complies with the above conditions except to the extent
         expressly waived in writing by the Board of Directors. In the event
         that the Employee shall be determined to be guilty of violation of any
         of the foregoing conditions by agreement or by the reasonable
         determination of the Board of Directors and the Employee does not
         correct such violation within a reasonable time, as determined by the
         Board after notice to him in writing, the Company may thereafter
         suspend or terminate in whole or in part any further payments under
         this Agreement.

         This Agreement shall not be deemed to modify in any way any agreement
         between the Company and the Employee concerning the protection of
         Company secrets.

IX)  DISSOLUTION, MERGER OR CONSOLIDATION

         If the Company shall at any time be merged or consolidated into or with
         any other corporation or corporations or if substantially all the
         assets of the Company are sold or otherwise transferred to another
         corporation or party, the provisions of this Agreement shall be binding
         upon and inure to the benefit of the corporation surviving or resulting
         from such merger or consolidation or to which such assets shall be sold
         or transferred, and this provision shall apply in the event of any
         subsequent sale, merger, consolidation or transfer.


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X)       NON-ASSIGNABILITY

         This Agreement shall be binding upon and inure to the benefit of the
         Parties hereto and to their successors. The Employee may not assign,
         pledge or otherwise encumber any rights or interest hereunder without
         the written consent of the Company. The Company may not assign this
         Agreement other than as set forth in IX above.

XI)      ENTIRE AGREEMENT OF THE PARTIES

         This Agreement expresses the entire agreement of the parties, and all
         promises, representations, understandings, arrangement and prior
         agreements are merged herein and superseded hereby.

XII)     AMENDMENTS, TERMINATION

         Except as herein provided, this Agreement cannot be terminated by
         unilateral action of either party. However, this Agreement can be
         changed, modified or terminated by mutual written agreement. No person,
         other than pursuant to a resolution of the Board of Directors of the
         Company, shall have any authority on behalf of the Company to agree to
         modify, change or terminate this Agreement or anything in reference
         thereto, and any such modification, change or termination must be in
         writing and signed by both parties.

XIII)    LAWS GOVERNING

         This Agreement has been entered into in the State of Ohio, and shall be
         construed, interpreted and governed in accordance with the laws of the
         State of Ohio.

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed by its
officers thereunto duly authorized, and the Employee has hereunto set his hand,
as of the day and year first above written.

                           KEITHLEY INSTRUMENTS, INC.

                           ("Company")

                           By  /s/ Joseph P. Keithley
                             -------------------------------------
                           (Chairman, Board of Directors and CEO)

                           And  /s/ RONALD M. REBNER
                              ------------------------------------
                           (CFO)

                           /s/ MARK J. PLUSH
                           ----------------------------------------
                           ("Employee")