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                                                                   EXHIBIT 10.13

                              EXECUTIVE AGREEMENT

     This Executive Agreement (this "Agreement") is made and entered into as of
the 25th day of June, 1997 (the "Effective Date") between Tuboscope Inc., a
Delaware corporation and its subsidiaries (collectively "Tuboscope") and Joseph
C. Winkler (the "Executive").

WHEREAS, the Executive is employed as an Executive Officer or Senior Manager of
Tuboscope; and

WHEREAS, the Board of Directors of the Company has authorized certain "Severance
and Change of Control Severance Protections" in order to retain and motivate
management and to ensure continuity of management; and

WHEREAS, Tuboscope believes it to be in the best interests of its stockholders
to attract, retain and motivate key executive officers and ensure continuity of
management; and

WHEREAS, it is in the best interest of Tuboscope and its stockholders if the key
executive officers can approach material business development decisions
objectively and without concern for their personal situation;

WHEREAS, Tuboscope recognizes that the possibility of a Change of Control of the
Corporation may result in the departure of key executives to the detriment of
Tuboscope and its stockholders;

     In consideration of Executive's continued employment as an executive
officer with Tuboscope and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, Tuboscope and
Executive agree as follows:

1.  Term of Agreement

    A.  This Agreement shall commence on the Effective Date and shall continue
        in effect, unless terminated earlier as otherwise set forth herein
        through December 31, 2002; provided, however, that unless so terminated
        earlier, the term of this Agreement shall automatically be extended for
        one or more additional terms of three (3) years; provided, however, this
        Agreement may be terminated at any time after the expiration of the
        original term upon Tuboscope providing three (3) years written notice to
        the Executive.

    B.  The term of this Agreement shall terminate upon the expiration of the
        "Severance Payout Period" or "Change in Control Payout Period", as
        applicable, and all rights or benefits thereunder have been satisfied.
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2.  Certain Definitions

    A.  "Cause".  "Cause" shall mean:
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        (i)    Executive's conviction of a felony involving moral turpitude,
               dishonesty or a breach of trust as regards Tuboscope;

        (ii)   Executive's commission of any act of theft, fraud, embezzlement
               or misappropriation against Tuboscope that is materially
               injurious to it regardless of whether a criminal conviction is
               obtained;

        (iii)  Executive's willful and continued failure to devote substantially
               all of his business time to the Corporation's business affairs
               (excluding failures due to illness, incapacity, vacations,
               incidental civic activities and incidental personal time) which
               failure is not remedied within a reasonable time after written
               demand is delivered by the Corporation, which demand specifically
               identifies the manner in which the Corporation, believes that
               Executive has failed to devote substantially all of his business
               time to the Corporation's business affairs; or

        (iv)   Executive's unauthorized disclosure of confidential information
               of Tuboscope that is materially injurious to Tuboscope.

     For purposes of this definition, no act, or failure to act, on Executive's
part shall be deemed "willful" unless done, or omitted to be done, by Executive
not in good faith and without reasonable belief that Executive's action or
omission was in the best interest of Tuboscope.

     B.  "Date of Termination" shall mean the date specified in the Notice of
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         Termination relating to termination of Executive's employment with
         Tuboscope; provided that such date shall not be less than 20 days nor
         more than 45 days following: (i) involuntary termination, not for
         cause, pursuant to Section 4 hereof, or (ii) the date within the
         Protective Period that Executive voluntarily terminates his employment
         for good reason so governed by Section 5 hereof.

     C.  "Executive Officer" shall mean an officer of the Company who is both a
          -----------------
         named executive officer of Tuboscope and a member of the Senior
         Management Team ("SMT").

     D.  "Executive" shall mean the named Executive Officer or Senior Manager
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         who is a party to this Agreement and in the event of the Executive's
         death after a "qualifying" termination pursuant to Section 4 hereof or
         a Change of Control pursuant to Section 5 hereof, then the term
         "Executive" shall include his estate.

     E.  "Good Reason" shall mean:
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         (i)  failure to re-elect or appoint the Executive to any corporate
              office or directorship held at the time of the Change of Control
              or a material reduction in Executive's authority, duties or
              responsibilities (including status, offices, titles and reporting
              requirements) or if Executive is assigned duties or
              responsibilities inconsistent in any material respect from those
              of Executive at the time of the relevant Change in Control all on
              the

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               basis of which Executive makes a good faith determination that
               the terms of his employment have been detrimentally and
               materially affected.

         (ii)  a material reduction of Executive's compensation or benefits,
               including annual base salary, annual bonus, intermediate or long-
               term cash or equity incentive opportunities or plans from those
               in effect prior to the Change in Control;

        (iii)  the Company fails to obtain a written agreement satisfactory to
               Executive from any successor or assigns of the Company to assume
               and perform this Agreement as provided in Section 9 hereof;

        (iv)   the Company requires Executive to be based at any office located
               more than fifty (50) miles from the Company's current offices
               without Executive's consent.

     F.  "Notice of Termination" shall mean a written notice delivered to the
         -----------------------
         other party indicating the specific termination provision in this
         Agreement relied upon for termination of Executive's employment and
         shall set forth in reasonable detail the facts and circumstances
         claimed to provide a basis for termination of Executive's employment
         under the provision so indicated.

     G.  "Option Plans" shall mean the Corporation's stock option plans,
         --------------
         incentive plans, equity participation plans, or other similar plans,
         and any stock option agreements or other agreements used in connection
         therewith.

     H.  "Senior Manager" shall mean a member of the SMT who is not an Executive
         ----------------
         Officer of the Company.

     I.  "Termination Base Salary" shall mean Executive's base salary at the
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         rate in effect at the time the Notice of Termination is given or, for
         purposes of a Change of Control, if a greater amount, Executive's base
         salary at the rate in effect immediately prior to the Change of
         Control.

3.  Termination for Cause.  Tuboscope may terminate Executive for Cause at any
time, including following a Change of Control, upon written notice to Executive.

4.  Standard Severance Plan.  If Executive is terminated involuntarily (i.e.,
without the consent of Executive) by Tuboscope for any reason other than for
Cause (and such termination is not pursuant to a Change of Control) the
Executive shall receive the following compensation and benefits from Tuboscope:

    A.  Tuboscope shall pay to Executive when otherwise due Executive's
        Termination Base Salary through the Date of Termination.

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    B. Effective as of the Date of Termination, Tuboscope shall continue to pay
       to Executive (the "Severance Pay") the Termination Base Salary, payable
       on a regular payroll basis, for a period of eighteen (18) months
       following the Date of Termination (such period to be herein referred to
       as the "Severance Payout Period"), subject to reduction as follows:

       (i)   If Executive is re-employed during the Severance Payout Period,
             Executive shall receive throughout the remainder of the Severance
             Payout Period following the effective date of such re-employment,
             50% of the Severance Pay otherwise due and payable to Executive
             after such date of re-employment;

       (ii)  In addition, if Executive is re-employed during the Severance
             Payout Period at an annual base salary that is less than the
             Termination Base Salary, in addition to the payment required by
             clause (i) above, Executive shall receive on a monthly basis
             throughout the remainder of the Severance Payout Period following
             the effective date of such re-employment the difference between (x)
             the salary actually received by Executive on a monthly basis from
             such re-employment and (y) the Termination Base Salary expressed as
             a monthly payment.


    C. Bonuses.

       (i)    Tuboscope shall pay to Executive the "target EV" (i.e., fifty
              percent (50%) of Executive's Termination Base Salary) of the
              annual bonus under the Corporation's "Annual Management Incentive
              Program" or a similar or successor plan for the year in which the
              Date of Termination occurred if Executive had not been so
              terminated.

       (ii)   Tuboscope shall pay to Executive any awards earned under the
              Company's "Value Plan", or a similar or successor long-term
              incentive plan adopted after the Effective Date, calculated
              through the last completed quarter prior to the Date of
              Termination, that Executive would have been entitled to receive
              for such period if Executive had not been so terminated.

       (iii)  All amounts due to Executive under this Section 4.C are due and
              payable on the normal distribution date for such bonuses for all
              other participants.

    D. All restricted shares and restricted stock units (including those under
       the Stock Match Program) of Executive shall be and become 100% vested
       and all restrictions thereon shall lapse as of the Date of Termination
       and the Corporation shall promptly deliver such shares to Executive;
       provided the Executive may elect to take a portion of the total shares
       on an annual basis for a maximum of five (5) years.

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5.  Change in Control Severance Plan. In the event that within the "Protective
    Period" (24 months following the Effective Date of a Change of Control)
    either (a) Executive voluntarily terminates employment for Good Reason or
    (b) Tuboscope terminates Executive's employment other than for Cause, the
    Executive shall receive the following compensation and benefits from
    Tuboscope:

    A.  Tuboscope shall pay to Executive when otherwise due Executive's
        Termination Base Salary through the Date of Termination.

    B.  Effective as of the Date of Termination, Tuboscope shall continue to pay
        to Executive the Termination Base Salary, payable on a regular payroll
        basis, for a period of twenty-four (24) months following the Date
        Termination (such period to be herein referred to as the "Change in
        Control Payout Period").

    C.  Effective as of the Date of Termination, Tuboscope shall pay to
        Executive an amount equal to two (2) times (i.e., the 24 months set
        forth in B above) fifty percent (50%) of Executive's Termination Base
        Salary ("Target EV") as payment for the "Annual Management Incentive
        Program". Payment shall be made in installments consistent with payment
        of the Executive's Termination Base Salary on a regular payroll basis.

    D.  Effective as of the Date of Termination, the performance awards for all
        overlapping periods of the Value Plan vest. For the year in which the
        Change of Control occurs, a full year is assumed to be completed for
        each performance period and included in the payoff calculations. Payout
        is prorated based on the number of deemed completed years in the
        performance periods. Payment is payable on the normal distribution date
        for such bonuses for all other participants.

E.  All restricted shares and restricted stock units (including those under the
    Stock Match Program) of Executive shall be and become 100% vested and all
    restrictions thereon shall lapse as of the Date of Termination and the
    Corporation shall promptly deliver such shares to Executive; provided the
    Executive may elect

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    to take a portion of the total shares on an annual basis for a maximum of
    five (5) years.

F.  Executive shall become and be fully vested in Executive's accrued benefits
    under all qualified pension, nonqualified pension, profit sharing, 401(k),
    deferred compensation and supplemental plans maintained by Tuboscope for
    Executive's benefit, except to the extent that the acceleration of vesting
    of such benefits would violate any applicable law or require Tuboscope to
    accelerate the vesting of the accrued benefits of all participants in such
    plan or plans, in which case Tuboscope shall pay Executive a lump sum
    payment, within 30 days following the Date of Termination, in an amount
    equal to the present value of such unvested accrued benefits. In addition,
    if such a lump sum payment is payable, Tuboscope shall make an additional
    gross-up payment to Executive in an amount such that the net amount of the
    lump sum payment and such additional gross-up payment retained by Executive,
    after the calculation and deduction of all federal, state and local income
    tax and employment tax (including any interest or penalties imposed with
    respect to such taxes) on such lump sum payment and additional gross-up
    payment, and taking into account any lost or reduced tax deductions on
    account of such gross-up payment, shall be equal to such lump sum payment.

6.  Additional Benefits.

    A.  For the term of the Severance Payout Period or Change in Control Payout
        Period, as applicable, Tuboscope shall continue to provide Executive and
        Executive's eligible family members, based on the cost sharing
        arrangement between Executive and Tuboscope on the Date of Termination,
        with medical and dental health benefits and disability coverage and
        benefits at least equal to those which would have been provided to
        Executive if Executive's employment had not been terminate or, if more
        favorable to Executive, as in effect generally at any time during such
        Severance Payout Period or Change in Control period, as applicable.
        Notwithstanding the foregoing, if Executive becomes re-employed and is
        eligible to receive medical, dental and disability benefits under
        another employer's plans, Tuboscope's obligations under this Section 6A
        shall be reduced to the extent comparable benefits are actually received
        by Executive during the Severance Payout Period or Change in Control
        Payout Period, as applicable, and any such benefits actually received by
        Executive shall be promptly reported by Executive to Tuboscope. In the
        event Executive is ineligible under the terms of Tuboscope's benefit
        plans or programs to continue to be so covered, Tuboscope shall provide
        Executive with substantially equivalent coverage through other sources
        or will provide Executive with a lump sum payment in such amount that,
        after all taxes on that amount, shall be equal to the cost to Executive
        of providing Executive such benefit coverage. The lump sum shall be
        determined on a present value basis using the interest rate provided in
        Section 1274(b)(2)(B) of the Internal Revenue Code of 1986, as amended
        (the "Code") on the Date of Termination. In addition, if such a lump sum
        payment is payable, Tuboscope shall make an

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        additional gross-up payment to Executive in an amount such that the net
        amount of the lump sums payment and such additional gross-up payment
        retained by Executive, after the calculation and deduction of all
        federal, state and local income tax and employment tax (including any
        interest or penalties imposed with respect to such taxes) on such lump
        sum payment and additional gross-up payment, and taking into account any
        lost or reduced tax deductions on account of such gross-up payment,
        shall be equal to such lump sum payment.

    B.  Outplacement Benefits.  Throughout the term of the Severance Payout
        ----------------------
        Period or Change in Control Payout Period, as applicable, Executive
        shall be entitled to receive outplacement services, payable by
        Tuboscope, with an aggregate cost not to exceed 15% of Executive's
        Termination Base Salary, with an executive outplacement service firm
        reasonably acceptable to Tuboscope and Executive.

    C.  Automobile Benefits.  Throughout the Severance Payout Period or Change
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        in Control Payout Period, as applicable, Tuboscope shall continue to pay
        to Executive the monthly car allowance payable to Executive as of the
        Date of Termination, payable on the regular payroll basis in effect for
        car allowances.

7.  Accelerated Vesting of Options Upon a Change of Control.

    Notwithstanding any provisions to the contrary of any of the Option Plans or
    Option Agreements, upon a Change in Control all outstanding unvested stock
    options, if any, granted to Executive under any of the Option Plans (or
    options substituted therefor covering the stock of a successor corporation)
    shall be and become fully vested and exercisable as to all shares of stock
    covered thereby effective as of the date of the Change in Control.

8.  Mitigation.

    Executive shall not be required to mitigate the amount of any payment
    provided for in this Agreement by seeking other employment or otherwise nor,
    except as provided in Section 4B and Section 6A, shall the amount of any
    payment or benefit provided for in this Agreement be reduced by any
    compensation earned or benefit received by Executive as the result of
    employment by another employer or self-employment, by retirement benefits,
    by offset against any amount claimed to be owed by Executive to Tuboscope or
    otherwise.

9.  Successor Agreement.

    Tuboscope will require any successor (whether direct or indirect, by
    purchase, merger, consolidation or otherwise) to all or substantially all of
    the business and/or assets of Tuboscope to assume expressly and agree to
    perform this Agreement in the same manner and to the same extent that the
    Companies would be required to perform if no succession had taken place.
    Failure of the successor to so assume shall constitute a breach of this

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     Agreement and entitle Executive to the benefits hereunder as if triggered
     by a termination not for good cause.

10.  Indemnity.

     In any situation where under applicable law Tuboscope has the power to
     indemnify, advance expenses to and defend Executive in respect of any
     judgements, fines, settlements, loss, cost or expense (including attorneys
     fees) of any nature related to or arising out of Executive's activities as
     an agent, employee, officer or director of Tuboscope or in any other
     capacity on behalf of or at the request of Tuboscope, then Tuboscope shall
     promptly on written request, indemnify Executive, advance expenses
     (including attorney's fees) to Executive and defend Executive to the
     fullest extent permitted by applicable law, including but not limited to
     making such findings and determinations and taking any and all such actions
     as Tuboscope may, under applicable law, be permitted to have the discretion
     to take so as to effectuate such indemnification, advancement or defense.
     Such agreement by Tuboscope shall not be deemed to impair any other
     obligation of Tuboscope respecting Executive's indemnification or defense
     otherwise arising out of this or any other agreement or promise of
     Tuboscope under any statute.

11.  Notice.

     For the purpose of this Agreement, notices and all other communications
     provided for in this Agreement shall be in writing and delivered by United
     States certified or registered mail (return receipt requested, postage
     prepaid) or by courier guaranteeing overnight delivery or by hand delivery
     (with signed receipt required), addressed to the respective addresses set
     forth below, and such notice or communication shall be deemed to have been
     duly given two days after deposit in the mail, one day after deposit with
     such overnight carrier or upon delivery with hand delivery.  The addresses
     set forth below may be changed by a writing in accordance herewith.

     Tuboscope:                     Executive:

     Tuboscope, Inc.                Joseph C. Winkler
     2835 Holmes Road               635 Lornmead
     Houston, Texas  77051          Houston, Texas 77024
     Attn:  Chief Executive Officer
     with a copy to General Counsel

12.  Dispute Resolution.

     If any dispute arises out of this Agreement, the "complaining party" shall
     give the "other party" written notice of such dispute.  The other party
     shall have ten (10) business days to resolve the dispute to the complaining
     party's satisfaction.  If the dispute is not resolved by the end of such
     period, the complaining party may by written notice (the "Notice")

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     demand arbitration of the dispute as set out below, and each party hereto
     expressly agrees to submit to, and be bound by, such arbitration.

     (a)  Each party will, within ten (10) business days of the Notice, nominate
          an arbitrator.  Each nominated arbitrator must be someone experienced
          in dispute resolution and of good character without moral turpitude
          and not within the employ or direct or indirect influence of the
          nominating party.  The two nominated arbitrators will, within ten (10)
          business days of nomination, agree upon a third arbitrator.  If two
          (2) appointed arbitrators cannot agree on a third arbitrator within
          such period, the parties may seek such an appointment through any
          permitted court proceeding or by the American Arbitration Association
          ("AAA").  The three arbitrators will set the rules and timing of the
          arbitration, but will generally follow the rules of the AAA and this
          Agreement where same are applicable and shall provide for written fact
          findings.

     (b)  The arbitration hearing will in no event take place more than ninety
          (90) days after the appointment of the third arbitrator.

     (c)  The arbitration will take place in Houston, Texas unless otherwise
          unanimously agreed to by the parties.

     (d)  The results of the arbitration and the decision of the arbitrators
          will be final and binding on the parties and each party agrees and
          acknowledges that these results shall be enforceable in a court of
          law.

13.  Governing Law.
     This Agreement will be governed by and construed in accordance with the
internal substantive laws, and not the choice of law rules, of the State of
Texas.

     IN WITNESS WHEREOF, Tuboscope and the Executive have executed this
Amendment to be effective the date first above written.

EXECUTIVE                           TUBOSCOPE INC.,
                                    a Delaware corporation


/s/ JOSEPH C. WINKLER                 BY /s/ JOHN F. LAULETTA
------------------------------               -----------------------------
    Joseph C. Winkler                        John F. Lauletta
                                             President and Chief Executive
                                             Officer

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