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                                                                   EXHIBIT 10.1

                         EXECUTIVE EMPLOYMENT AGREEMENT

This Executive Employment Agreement ("Agreement"), including the attached
Exhibit A, is entered into between NATCO Group Inc., a Delaware corporation,
having offices at 2950 N. Loop West, Suite 700, Houston, Texas 77092
("Company"), and John U. Clarke, an individual residing in Houston, Texas
("Employee"), to be effective as of December 7, 2004 (the "Effective Date").

Company is desirous of securing the services of Employee pursuant to the terms
and conditions and for the consideration set forth in this Agreement, and
Employee is desirous of entering employment with the Company or a subsidiary
thereof pursuant to such terms and conditions and for such consideration.
Therefore, for and in consideration of the mutual promises, covenants, and
obligations contained herein, Company and Employee agree as follows:

                        ARTICLE 1: EMPLOYMENT AND DUTIES

         1.1. Company shall employ, or shall cause a subsidiary to employ,
Employee, and Employee shall be employed by Company or such subsidiary,
beginning as of the Effective Date of this Agreement and continuing until the
date set forth on Exhibit A (the "Term"), subject to the terms and conditions
of this Agreement. This Agreement will expire by its own terms and the Employee
will automatically become an employee at will and be included in all general
employment and benefit arrangements at the end of the Term unless the Company
notifies Employee of its intention to extend the Term (such notice to include
the length of the intended extension) at least 60 days prior to the expiration
of the Term and Employee accepts such extension within 10 days of receipt of
such notice.

         1.2. Employee shall be employed in the position(s) set forth on
Exhibit A. Employee agrees to serve in the assigned position(s) and to perform
diligently and to the best of Employee's abilities the duties and services
appertaining to such position as determined by Company, as well as such
additional or different duties and services appropriate to such position which
Employee from time to time may be reasonably directed to perform by Company.
Employee shall at all times comply with and be subject to such policies and
procedures as Company may establish from time to time.

         1.3. Employee shall, during the period of Employee's employment by
Company or a subsidiary, devote Employee's full business time, energy, and best
efforts to the business and affairs of Company and its subsidiaries and
affiliated entities. Employee may not engage, directly or indirectly, in any
other business, investment, or activity that interferes with Employee's
performance of Employee's duties hereunder, is contrary to the interests of
Company, or requires any significant portion of Employee's business time. The
activities described as "permitted activities" on Exhibit A shall not be deemed
a violation of this Section 1.3.

         1.4. Employee acknowledges and agrees that Employee owes a fiduciary
duty of loyalty, fidelity and allegiance to act at all times in the best
interests of Company and its subsidiaries and to do no act which would injure
Company's business, its interests or its reputation. Employee agrees to comply
with the policies and procedures as described and contained in Company's
Business Ethics Policies and related policies, copies of which have been
provided to Employee.

                      ARTICLE 2: COMPENSATION AND BENEFITS

         2.1. Employee shall be paid base salary and bonus and shall accrue
vacation as set forth on Exhibit A. Employee's base salary shall be paid in
bi-weekly installments in accordance with Company's or the employing
subsidiary's standard payroll practice, and (as with all other payments made to
Employee by Company or such subsidiary) is subject to withholding of all
federal, state, city or other taxes as may be required by law.

         2.2. While employed by Company or a subsidiary (both during the Term
and thereafter), Employee shall be allowed to participate, on the same basis
generally as other employees of Company or such subsidiary, in all general
employee benefit plans and programs, including improvements or modifications of
the same, which on the effective date or thereafter are made available by
Company or such subsidiary to all or substantially all of its or their
employees. Such benefits, plans and programs may include, without limitation,
medical, dental care, life insurance, disability protection

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and qualified plans. Nothing in this Agreement is to be construed or
interpreted to provide greater rights, participation, coverage or benefits
under such benefit plans or programs than provided to similarly situated
employees pursuant to the terms and conditions of such benefit plans and
programs, except as may be approved by Company's Governance, Nominating &
Compensation Committee (or successor committee with responsibility for the
compensation function) and/or Board of Directors.

         2.3. Employee shall receive the grants and awards of restricted stock
and options as, and on the dates specified in Exhibit A, subject to his
continued employment on the date of grant. Employee shall be eligible to
participate in the Company's long-term incentive plans and Company's annual
incentive plan currently maintained or hereafter maintained by Company or a
subsidiary for its officers as a group. Any such grants, awards or
participation shall be subject to separate agreements containing the terms and
provisions applicable to each such grant, award or participation as provided in
the applicable incentive plan and by the committee administering such plan.

         2.4. Company shall not by reason of this Article 2 be obligated to
institute, maintain or refrain from changing, amending or discontinuing, any
such incentive compensation or employee benefit program or plan, so long as
such actions or inactions are similarly applicable to covered employees
generally. Moreover, unless specifically provided for in a written plan
document adopted by the Board of Directors of Company, none of the benefits or
arrangements described in this Article 2 shall be secured or funded in any way,
and each shall instead constitute an unfunded and unsecured promise to pay
money in the future exclusively from the general assets of Company.

         2.5. Company may withhold from any compensation, benefits or amounts
payable under this Agreement all federal, state, city or other taxes as may be
required by law.

         2.6. Company shall pay up to $2,500 in moving expenses to move
Employee's office furniture and effects to the Company's headquarters. Such
personal items shall remain the property of Employee.

                                   ARTICLE 3:
    TERMINATION PRIOR TO EXPIRATION OF TERM AND EFFECTS OF SUCH TERMINATION

         3.1. Notwithstanding any other provisions of this Agreement, Company
shall have the right to terminate Employee's employment under this Agreement at
any time prior to the expiration of the Term for any of the following reasons:

                  (a) For "cause" upon the determination by the Company's
         independent directors of the Board who are neither employees of nor
         Affiliated with Company or any subsidiary of Company apart from his or
         her capacity as a member of the Board and any Board committee and who
         otherwise have no interest in such determination ("Independent
         Directors") that "cause" exists for the termination of the employment
         relationship. As used in this Section 3.1(a), the term "cause" shall
         mean (i) Employee's gross negligence or willful misconduct in the
         performance of the duties and services required of Employee pursuant
         to this Agreement; or (ii) Employee's final conviction of a felony or
         of a misdemeanor involving moral turpitude; (iii) Employee's
         involvement in a conflict of interest as referenced in Sections 1.3
         and 1.4 with respect to which Company makes a good faith determination
         to terminate the employment of Employee; or (iv) Employee's material
         breach of any material provision of this Agreement which remains
         uncorrected for 30 days following written notice to Employee by
         Company of such breach. It is expressly acknowledged and agreed that
         the decision as to whether "cause" exists for termination of the
         employment relationship by Company is delegated to the Independent
         Directors of the Board of Company for determination;

                  (b) For any other reason whatsoever, with or without cause,
         in the sole discretion of the Company's Independent Directors of the
         Board;

                  (c) Upon Employee's death; or

                  (d) To the extent allowed by law, upon Employee's becoming
         incapacitated by accident, sickness or other circumstance which
         renders him or her mentally or physically incapable of performing the
         duties and services required of Employee, as determined in good faith
         by Company.


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The termination of Employee's employment by Company prior to the expiration of
the Term shall constitute a "Termination for Cause" if made pursuant to Section
3.1(a); the effect of such termination is specified in Section 3.4. The
termination of Employee's employment by Company prior to the expiration of the
Term shall constitute an "Involuntary Termination" if made pursuant to Section
3.1(b); the effect of such termination is specified in Section 3.6(a). The
effect of the employment relationship being terminated pursuant to Section
3.1(c) or (d) as a result of Employee's death or disability is specified in
Section 3.6(b).

         3.2. Notwithstanding any other provisions of this Agreement except
Section 8.5, Employee shall have the right to terminate the employment
relationship under this Agreement at any time prior to the expiration of the
Term of employment for any of the following reasons:

                  (a) A material breach by Company of any material provision of
         this Agreement or the occurrence of an Involuntary Termination as
         defined in Section 3.5 which remains uncorrected for 30 days following
         written notice of such breach by Employee to Company; or

                  (b) For any other reason whatsoever, in the sole discretion
         of Employee.

The termination of Employee's employment by Employee prior to the expiration of
the Term shall constitute an "Involuntary Termination" if made pursuant to
Section 3.2(a); the effect of such termination is specified in Section 3.6(a).
The termination of Employee's employment by Employee prior to the expiration of
the Term shall constitute a "Voluntary Termination" if made pursuant to Section
3.2(b); the effect of such termination is specified in Section 3.3.

         3.3. Upon a "Voluntary Termination" of the employment relationship by
Employee prior to expiration of the Term, all future compensation to which
Employee would have been entitled and all future benefits for which Employee
would have been eligible shall cease and terminate as of the date of
termination. Employee shall be entitled to pro rata salary and accrued benefits
through the date of such termination, but Employee shall not be entitled to any
bonuses or incentive compensation not yet paid at the date of such termination.

         3.4. If Employee's employment hereunder shall be terminated by Company
for Cause prior to expiration of the Term, all future compensation to which
Employee would have been entitled and all future benefits for which Employee
would have been eligible shall cease and terminate as of the date of
termination. Employee shall be entitled to pro rata salary and accrued benefits
through the date of such termination, but Employee shall not be entitled to any
bonuses or incentive compensation not yet paid at the date of such termination.

         3.5. As used in this Agreement, "Involuntary Termination" shall also
mean termination of Employee's employment with Company if such termination
results from termination by Employee within 90 days of and in connection with
or based upon any of the following:

                  (a) A substantial and/or material reduction in the nature or
         scope of Employee's duties and/or responsibilities as such duties are
         constituted as of the effective date of this Agreement or later agreed
         to by Employee and Company, or if Employee is no longer an executive
         officer of the Company as defined as Section 16b in SEC regulations,
         which reduction remains in place and uncorrected for 30 days following
         written notice of such breach to Company by Employee;

                  (b) A reduction in Employee's base pay (except as part of a
        general cutback for all employees or officers);

                  (c) A change in the location for the primary performance of
         Employee's services under this Agreement from the city in which
         Employee was serving at the time of notification to a city which is
         more than 100 miles away from such location, which change is not
         approved by Employee.

                  3.6. Upon any Involuntary Termination of the employment
relationship by either Company or Employee prior to expiration of the Term,
Employee shall be entitled to receive pro rata base salary and benefits
(including payment for accrued, but unused, vacation) through the date of
termination. Depending upon the type of Involuntary Termination, Employee or
his estate may be entitled to additional compensation and/or benefits, as
described below.


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                  (a) Upon an Involuntary Termination of the employment
         relationship by either Company or Employee prior to expiration of the
         Term pursuant to Section 3.1(b), 3.2(a) or 3.5, Employee shall be
         entitled, after execution of a Waiver and Release Agreement in
         consideration of Employee's continuing obligations hereunder after
         such termination (including, without limitation, Employee's
         non-competition obligations), to (i) the sum of one year's annual base
         salary payable as follows: half of the base salary shall be paid
         within 30 days of the termination date; the remaining half shall be
         paid at the end of the 6-month period following the termination date;
         (ii) the amount of the target bonus compensation earned by Employee
         under any applicable bonus plan then in effect in accordance with its
         terms through the date of termination, based on Company performance
         through such date and prorated by multiplying such bonus compensation
         by the fraction obtained by dividing the number of days in the year
         through the date of termination by 365, payable as follows: half of
         target bonus amount shall be paid within 30 days of the termination
         date; the remaining half shall be paid at the end of the 6-month
         period following the termination date; (iii) the continuation of the
         provision of health insurance, dental insurance and life insurance
         benefits for a period of one year following the date of termination to
         Employee and Employee's family at least equivalent to and to the same
         extent as those which would have been provided to them in accordance
         with this Employment Agreement and the plans, programs, practices and
         policies of Company as in effect and applicable generally to other
         peer executives and their families at the date of termination, at the
         election of Employee; provided, however, that if the Employee becomes
         re-employed with another employer and is eligible to receive medical
         or other welfare benefits under another employer provided plan, the
         medical and other welfare benefits described herein will be secondary
         to those provided under such other plan during such applicable period
         of eligibility; and (iv) any bonus compensation that has been earned
         under the bonus plan, the payment of which has been deferred under the
         terms of the bonus plan, will be paid to Employee in accordance with
         the terms of the bonus plan.

                  (b) Upon an Involuntary Termination of the employment
         relationship by either Company or Employee prior to expiration of the
         Term pursuant to Section 3.1(c) or (d), Employee or his beneficiary's
         shall be entitled to (i) cash in the amount of the target bonus
         compensation earned by Employee under any applicable bonus plan then
         in effect in accordance with its terms through the date of
         termination, based on Company performance through such date and
         prorated by multiplying such bonus compensation by the fraction
         obtained by dividing the number of days in the year through the date
         of termination by 365, payable no later than 90 days following the
         date of termination; and (ii) any bonus compensation that has been
         earned under the bonus plan, the payment of which has been deferred
         under the terms of the bonus plan, will be paid to Employee in
         accordance with the terms of the bonus plan.

                  (c) Upon an Involuntary Termination of the employment
         relationship by either Company or Employee prior to expiration of the
         Term pursuant to Section 3.1(b), 3.2(a) or 3.5 within 12 months
         following a Change of Control, Employee shall be entitled, after
         execution of a Waiver and Release Agreement in consideration of
         Employee's continuing obligations hereunder after such termination
         (including, without limitation, Employee's non-competition
         obligations), (i) to the sum of 1.5 times one year's annual base
         salary payable as follows: half of the base salary shall be paid
         within 30 days of the termination date; the remaining half shall be
         paid at the end of the 6-month period following the termination date;
         (ii) a lump sum cash amount equal to the product of 1.5 times the
         target bonus compensation at the greater of (A) the target bonus
         compensation in effect at the time notice of termination is given or
         (B) the target bonus compensation in effect immediately preceding the
         Change of Control Date, payable as follows: half of target bonus
         amount shall be paid within 30 days of the termination date; the
         remaining half shall be paid at the end of the 6-month period
         following the termination date; (iii) the continuation of the
         provision of health insurance, dental insurance and life insurance
         benefits for a period of 18 months following the date of termination
         to Employee and Employee's family at least equivalent to and to the
         same extent as those which would have been provided to them in
         accordance with this Employment Agreement and the plans, programs,
         practices and policies of Company as in effect and applicable
         generally to other peer executives and their families at the date of
         termination, at the election of Employee, or the cash-equivalent
         thereof; provided, however, that if the Employee becomes re-employed
         with another employer and is eligible to receive medical or other
         welfare benefits under another employer provided plan, the medical and
         other welfare benefits described herein will be secondary to those
         provided under such other plan during such applicable period of
         eligibility; and (iv) any bonus compensation


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         that has been earned under the bonus plan, the payment of which has
         been deferred under the terms of the bonus plan, will be paid to
         Employee in accordance with the terms of the bonus plan. In addition,
         notwithstanding the terms of the any related incentive plan or
         agreement, or any award agreement evidencing awards of stock options
         or restricted stock to purchase stock of Company, in the event of a
         Change of Control while Employee is employed by Company, all
         outstanding stock options held by Employee shall fully vest as of the
         Change of Control Date and become immediately exercisable in
         accordance with their terms and all restrictions on any restricted
         stock of Company held by Employee shall lapse as of the Change of
         Control Date, and any such stock options shall be exercisable for 12
         months after the date of termination, unless the term of the stock
         options expires before the end of such longer period, in which case
         the stock option shall be exercisable until the expiration of its
         term.

                  (d) Upon an Involuntary Termination of the employment
         relationship by either Company or Employee prior to expiration of the
         Term pursuant to Section 3.1(b), 3.2(a) or 3.5 within 6 months prior
         to a Change of Control, Employee shall be entitled, after execution of
         a Waiver and Release Agreement in consideration of Employee's
         continuing obligations hereunder after such termination (including,
         without limitation, Employee's non-competition obligations), (i) to
         the sum of 1.5 times one year's annual base salary payable as follows:
         the full amount of such payment shall be paid at the end of the
         6-month period following the termination date, with the amount of such
         payment to be offset by any payment Employee has previously received
         under Section 3.6(a)(i); (ii) a lump sum cash amount equal to the
         product of 1.5 times the target bonus compensation at the greater of
         (A) the target bonus compensation in effect at the time notice of
         termination is given or (B) the target bonus compensation in effect
         immediately preceding the Change of Control Date, payable as follows:
         the full amount of such payment shall be paid at the end of the
         6-month period following the termination date, with the amount of such
         payment to be offset by any payment Employee has previously received
         under Section 3.6(a)(ii); (iii) the continuation of the provision of
         health insurance, dental insurance and life insurance benefits for a
         period of 18 months following the date of termination to Employee and
         Employee's family at least equivalent to and to the same extent as
         those which would have been provided to them in accordance with this
         Employment Agreement and the plans, programs, practices and policies
         of Company as in effect and applicable generally to other peer
         executives and their families at the date of termination, at the
         election of Employee, or the cash-equivalent thereof; provided,
         however, that if the Employee becomes re-employed with another
         employer and is eligible to receive medical or other welfare benefits
         under another employer provided plan, the medical and other welfare
         benefits described herein will be secondary to those provided under
         such other plan during such applicable period of eligibility; and (iv)
         any bonus compensation that has been earned under the bonus plan, the
         payment of which has been deferred under the terms of the bonus plan,
         will be paid to Employee in accordance with the terms of the bonus
         plan. In addition, Employee shall receive a cash payment, (x) with
         respect to any stock option that is forfeited as of the date of his
         termination of employment, equal to the difference between the closing
         price of the Company stock as of the Change of Control Date and such
         option's exercise price (or, if the term of such option would have
         expired before the Change of Control Date, the difference between the
         closing price of the Company stock as of the date of such option's
         expiration date and such option's exercise price) and (y) with respect
         to any restricted stock that is forfeited as of the date of his
         termination of employment, equal to the closing price of such stock as
         of the Change of Control Date, with such payment to be made within 30
         days of the Change of Control Date.

                  (e) "Change of Control" of Company shall occur if: (1)
         Company merges or consolidates with any other entity (other than one
         of NATCO Group Inc.'s majority owned subsidiaries) and the
         shareholders of NATCO Group Inc. own less than 50% of the surviving
         entity; (2) Company sells all or substantially all of its assets to
         any other person or entity (other than (i) a sale of equity interests
         in NATCO Group Inc. or (ii) a sale of assets to another majority owned
         subsidiary of NATCO Group Inc. and in connection therewith Employee
         becomes employed by such subsidiary, NATCO Group Inc. or a partnership
         in which NATCO Group Inc. is the general partner); (3) Company is
         dissolved or liquidated; (4) any third person or entity together with
         its Affiliates (including a "group" as contemplated by Paragraph
         13(d)(3) of the Securities Exchange Act of 1934, as amended) shall
         become, directly or indirectly, the Beneficial Owner of greater than
         50% of the voting stock of Company, based upon voting power (except as
         the result of a distribution of the voting securities of the Company
         to the shareholders); or (5) during such time as Company has a class
         of Voting Securities registered under the Securities Exchange Act of
         1934, the individuals who constituted the members of the Company's
         Board of Directors ("Incumbent Board") upon the effective date of such
         registration cease for any reason to


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         constitute at least a majority thereof, provided that any person
         becoming a director whose election or nomination for election by
         Company stockholders was approved by a vote of at least two-thirds of
         the directors 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, for purposes of this subclause (5),
         considered as though such person were a member of the Incumbent Board.

                  (f) "Change of Control Date" shall mean the day on which a
         Change of Control becomes effective.

                  (g) Employee shall not be under any duty or obligation to
         seek or accept other employment following Involuntary Termination and,
         except as provided in Section 6.2, the amounts due Employee hereunder
         shall not be reduced or suspended if Employee accepts subsequent
         employment. Employee's rights under this Section 3.6 are Employee's
         sole and exclusive rights against Company, or its Affiliates, and
         Company's sole and exclusive liability to Employee under this
         Agreement, in contract, tort, or otherwise, for any Involuntary
         Termination of the employment relationship. Employee, to the extent
         permitted by law, covenants not to sue or lodge any claim, demand or
         cause of action against Company for any sums for Involuntary
         Termination other than those sums specified in this Section 3.6.

         3.7. In all cases, the payments payable to Employee under Section 3.6
of this Agreement upon termination of the employment relationship shall be
offset against any amounts to which Employee may otherwise be entitled under
any and all severance plans and policies of Company, or its Affiliates.

         3.8. Termination (including expiration of the Term) of the employment
relationship does not terminate those obligations imposed by this Agreement,
which are continuing obligations, including, without limitation, Employee's
obligations under Articles 5 and 6. Upon termination, Employee shall promptly
return all property of the Company and its Affiliates to the Company, including
books, records, computer files, etc.

         3.9. Limitation of Benefits.

                  (a) Anything in this Agreement to the contrary
         notwithstanding, in the event it shall be determined that any benefit,
         payment or distribution by Company to or for the benefit of Employee
         (whether payable or distributable pursuant to the terms of this
         Agreement or otherwise) (a "Payment") would, if paid, be subject to
         the excise tax imposed by Section 4999 of the Code (the "Excise Tax"),
         then the Payment shall be reduced to the extent necessary to avoid the
         imposition of the Excise Tax. Company may select the Payments to be
         limited or reduced.

                  (b) All determinations required to be made under this Section
         3.9, including whether an Excise Tax would otherwise be imposed and
         the assumptions to be utilized in arriving at such determination,
         shall be made by Independent Tax Counsel which shall provide detailed
         supporting calculations both to Company and Employee within 15
         business days of the receipt of notice from Employee that a Payment is
         due to be made, or such earlier time as is requested by Company. For
         purposes of this paragraph, "Independent Tax Counsel" will mean a
         lawyer, a certified public accountant with a nationally recognized
         accounting firm, or a compensation consultant with a nationally
         recognized actuarial and benefits consulting firm with expertise in
         the area of executive compensation, who will be selected by Company
         and will be reasonably acceptable to Employee, and whose fees and
         disbursements will be paid by Company. Any determination by the
         Independent Tax Counsel shall be binding upon Company and Employee.
         If, as a result of any uncertainty in the application of Section 4999
         of the Code at the time the initial determination is made by the
         Independent Tax Counsel hereunder, Payments hereunder have been
         unnecessarily limited by this Section 3.9 ("Underpayment"), consistent
         with the calculations required to be made hereunder, then the
         Independent Tax Counsel shall determine the amount of the Underpayment
         that has occurred and any such Underpayment shall be properly paid by
         Company to or for the benefit of Employee. If, however, Payments
         hereunder have not been sufficiently limited by this Section 3.9,
         consistent with the calculations required to be made hereunder, to
         prevent the imposition of an Excise Tax upon Employee (the
         "Overpayment"), then Employee shall notify Company in writing within
         15 days of any claim by the Internal Revenue Service, that, if
         successful, would require the payment by Employee of any Excise Tax,


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         and the Independent Tax Counsel shall determine the amount of
         Overpayment that has occurred and any such Overpayment shall be
         properly refunded by Employee by or for the benefit of Company so as
         to properly prevent the imposition of the Excise Tax.

                                   ARTICLE 4:
CONTINUATION OF EMPLOYMENT BEYOND TERM; TERMINATION AND EFFECTS OF TERMINATION

         4.1. Should Employee remain employed by Company or a subsidiary beyond
the expiration of the Term of this Agreement, and this Agreement has not been
extended by Company, the employer-employee relationship shall be employment at
will, terminable at any time by either Company, its employing subsidiary or
Employee for any reason whatsoever, with or without cause.

         ARTICLE 5: OWNERSHIP AND PROTECTION OF INFORMATION; COPYRIGHTS

         5.1. All information, ideas, concepts, improvements, discoveries, and
inventions, whether patentable or not, which are conceived, made, developed or
acquired by Employee, individually or in conjunction with others, during
Employee's employment by Company or a subsidiary (whether during business hours
or otherwise and whether on Company's premises or otherwise) which relate to
Company's or such subsidiary's business, products or services (including,
without limitation, all such information relating to corporate opportunities,
research, financial and sales data, pricing and trading terms, evaluations,
opinions, interpretations, acquisition prospects, the identity of customers or
their requirements, the identity of key contacts within the customer's
organizations or within the organization of acquisition prospects, or marketing
and merchandising techniques, prospective names, and marks) shall be disclosed
to Company and are and shall be the sole and exclusive property of Company or
its subsidiary. Moreover, all drawings, memoranda, notes, records, files,
correspondence, drawings, manuals, models, specifications, computer programs,
maps and all other writings or materials of any type embodying any of such
information, ideas, concepts, improvements, discoveries and inventions are and
shall be the sole and exclusive property of Company or its subsidiary.

         5.2. Employee acknowledges that the business of Company and its
Affiliates is highly competitive and that its strategies, methods, books,
records and documents, its technical information concerning its products,
equipment, services, and processes, procurement procedures and pricing
techniques, the names of and other information (such as credit and financial
data) concerning its customers and business affiliates, all comprise
confidential business information and trade secrets which are valuable, special
and unique assets which Company or its Affiliates use in its or their business
to obtain a competitive advantage over its or their competitors. Employee
further acknowledges that protection of such confidential business information
and trade secrets against unauthorized disclosure and use is of critical
importance to Company and its Affiliates in maintaining its and their
competitive position. Employee acknowledges that under this Agreement, Employee
is being given access to confidential business information and trade secrets of
Company and its Affiliates, and Employee hereby agrees that Employee will not,
at any time during or after his or her employment by Company, make any
unauthorized disclosure of any confidential business information or trade
secrets of Company or its Affiliates, or make any use thereof, except in the
carrying out of his or her employment responsibilities hereunder, or as may be
required by law. NATCO Group Inc. and its Affiliates shall be third party
beneficiaries of Employee's obligations under this Section. As a result of
Employee's employment by Company or a subsidiary, Employee may also from time
to time have access to, or knowledge of, confidential business information or
trade secrets of third parties, such as customers, suppliers, partners,
joint-venturers and the like, of Company and its Affiliates. Employee also
agrees to preserve and protect the confidentiality of such third-party
confidential information and trade secrets to the same extent, and on the same
basis, as confidential business information and trade secrets of the Company
and its Affiliates. Employee acknowledges that money damages would not be a
sufficient remedy for any breach of this Article 5 by Employee, and Company
shall be entitled to enforce the provisions of this Article 5 to specific
performance and injunctive relief as remedies for such breach or any threatened
breach. Such remedies shall not be deemed the exclusive remedies for a breach
of this Article 5, but shall be in addition to all remedies available at law or
in equity to Company, including the recovery of damages from Employee and his
or her agents involved in such breach.

             ARTICLE 6: POST-EMPLOYMENT NON-COMPETITION OBLIGATIONS

         6.1. As part of the consideration for the compensation and benefits to
be paid to Employee hereunder, and as an additional incentive for Company to
enter into this Agreement, and in particular Company's agreement to the
protections contained in Section 3.6, Company and Employee agree to the
non-competition provisions of this Article 6


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during the term of this Agreement. Employee agrees that during the period of
Employee's non-competition obligations hereunder, Employee will not, directly
or indirectly for Employee or for others, in any geographic area or market
where Company or any of its Affiliated companies are conducting any business as
of the date of termination of the employment relationship or have during the
previous 12 months conducted any business:

                  (a) engage in any business competitive with the business
         conducted by Company or its Affiliates;

                  (b) render advice or services to, or otherwise assist, any
         other person, association or entity who is engaged, directly or
         indirectly, in any business competitive with the business conducted by
         Company or its Affiliates; or

                  (c) induce any employee of Company or any of its Affiliates
         to terminate his or her employment with Company or its Affiliates, or
         hire or assist in the hiring of any such employee by person,
         association, or entity not Affiliated with Company or its Affiliates.
         These non-competition obligations shall continue for a period of one
         year after termination of this employment relationship.

         6.2. Employee understands that the foregoing restrictions may limit
his or her ability to engage in certain businesses during the 12-month period
provided for above, but acknowledges that Employee will receive sufficiently
high remuneration and other benefits under this Agreement to justify such
restriction. Employee acknowledges that money damages would not be sufficient
remedy for any breach of this Article 6 by Employee, and Company shall be
entitled to enforce the provisions of this Article 6 by terminating any
payments then owed to Employee under this Agreement and/or to specific
performance and injunctive relief as remedies for such breach or any threatened
breach. Such remedies shall not be deemed the exclusive remedies for a breach
of this Article 6, but shall be in addition to all remedies available at law or
in equity to Company, including, without limitation, the recovery of damages
from Employee and his or her agents involved in such breach.

         6.3. It is expressly understood and agreed that Company and Employee
consider the restrictions contained in this Article 6 to be reasonable and
necessary to protect the proprietary information of Company. Nevertheless, if
any of the aforesaid restrictions are found by a court having jurisdiction to
be unreasonable, or overly broad as to geographic area or time, or otherwise
unenforceable, the parties intend for the restrictions therein set forth to be
modified by such courts so as to be reasonable and enforceable and, as so
modified by the court, to be fully enforced.

                           ARTICLE 7: INDEMNIFICATION

         7.1 If, at any time during or after the Term of this Agreement,
Employee is made a party to, or is threatened to be made a party in, any civil,
criminal or administrative action, suit or proceeding by reason of the fact
that Employee is or was a director, officer, employee or agent of Company, or
of any other corporation or any partnership, joint venture, trust or other
enterprise for which Employee served as such at the request of Company, then
Employee shall be indemnified by Company, to the fullest extent permitted under
applicable law, against expenses actually and reasonably incurred by Employee
or imposed on Employee in connection with, or resulting from, the defense of
such action, suit or proceeding, or in connection with, or resulting from, any
appeal therein if Employee acted in good faith and in a manner Employee
reasonably believed to be in or not opposed to the best interest of Company,
and, with respect to any criminal action or proceeding, had no reasonable cause
to believe Employee's conduct was unlawful, except with respect to matters as
to which it is adjudged that Employee is liable to Company or to such other
corporation, partnership, joint venture, trust or other enterprise for gross
negligence or willful misconduct in the performance of the Employee's duties.
As used herein, the term "expenses" shall include all obligations actually and
reasonably incurred by the Employee for the payment of money, including,
without limitation, attorney's fees, judgments, awards, fines, penalties and
amounts paid in satisfaction of a judgment or in settlement of any such action,
suit or proceeding, except amounts paid to Company or such other corporation,
partnership, joint venture, trust or other enterprise by Employee. The
foregoing indemnification provisions shall be in addition to any other rights
to indemnification to which Employee may be entitled under any officers' and
directors' liability insurance maintained by Company or pursuant to any
separate agreement between Employee and Company with respect to
indemnification.


                                                                              8

<PAGE>

                            ARTICLE 8: MISCELLANEOUS

         8.1.     The following terms shall have the meanings ascribed to them
below for purposes of this Agreement:

                  (a) "Affiliates" or "Affiliated" means an entity who
         directly, or indirectly through one or more intermediaries, controls,
         is controlled by, or is under common control with Company.

                  (b) "Involuntary  Termination Date" shall mean Employee's last
         date of employment by reason of an Involuntary Termination.

         8.2. For purposes of this Agreement, notices and all other
communications provided for herein shall be in writing and shall be deemed to
have been duly given when personally delivered or when mailed by United States
registered or certified mail, return receipt requested, postage prepaid,
addressed as follows: If to Company, to:

         NATCO Group Inc.
         2950 N. Loop West
         Houston, Texas 77092
         Attention: Chairman of the Governance,
                    Nominating & Compensation Committee

If to Employee, to:

         John U. Clarke
         3850 Del Monte
         Houston, Texas 77019

Either Company or Employee may furnish a change of address to the other in
writing in accordance herewith, except that notices of changes of address shall
be effective only upon receipt.

         8.3. This Agreement shall be governed in all respects by the laws of
the State of Texas, excluding any conflict-of-law rule or principle that might
refer the construction of the Agreement to the laws of another state or
country.

         8.4. No failure by either party hereto at any time to give notice of
any breach by the other party of, or to require compliance with, any condition
or provision of this Agreement shall be deemed a waiver of similar or
dissimilar provisions or conditions at the same or at any prior or subsequent
time.

         8.5. If a dispute arises out of or related to this Agreement, other
than a dispute regarding Employee's obligations under Article 5, Section 5.2,
or Article 6, Section 6.1, and if the dispute cannot be settled through direct
discussions, then Company and Employee agree to first endeavor to settle the
dispute in an amicable manner by mediation, before having recourse to any other
proceeding or forum. Thereafter, the matter shall be submitted to binding
arbitration as follows:

         ANY DISPUTE, CLAIM, OR CONTROVERSY ARISING OUT OF OR RELATED IN ANY
WAY TO THIS AGREEMENT, INCLUDING BUT NOT LIMITED TO ITS ENFORCEABILITY,
VALIDITY, OR INTERPRETATION, OR RELATED IN ANY WAY TO EMPLOYEE'S EMPLOYMENT
WITH COMPANY OR A SUBSIDIARY THAT IS NOT FIRST RESOLVED BY AGREEMENT OR
MEDIATION AS PROVIDED ABOVE, SHALL BE SUBMITTED TO AND RESOLVED BY BINDING
ARBITRATION WITH THE AMERICAN ARBITRATION ASSOCIATION ("AAA") IN HOUSTON,
TEXAS, IN ACCORDANCE WITH THE AAA'S APPLICABLE RULES TO THE RESOLUTION OF
EMPLOYMENT DISPUTES. JUDGMENT UPON THE AWARD RENDERED BY THE ARBITRATOR(S) MAY
BE ENTERED IN ANY COURT HAVING JURISDICTION. IT IS SPECIFICALLY AGREED THAT THE
ARBITRATION PROVISION SHALL BE BINDING ON EMPLOYEE'S HEIRS, ADMINISTRATORS, AND
PERSONAL REPRESENTATIVES. THE PARAGRAPH SHALL BE GOVERNED BY THE FEDERAL
ARBITRATION ACT. NOTHING CONTAINED IN THE AGREEMENT SHALL PREVENT COMPANY FROM
SEEKING INJUNCTIVE RELIEF AGAINST EMPLOYEE FOR VIOLATION OF ANY AGREEMENT
PERTAINING TO NON-COMPETITION, TRADE SECRETS OR CONFIDENTIALITY.

Company shall pay all costs of such mediation and binding arbitration,
exclusive of Employee's legal fees.

         8.6. It is a desire and intent of the parties that the terms,
provisions, covenants and remedies contained in


                                                                              9

<PAGE>

this Agreement shall be enforceable to the fullest extent permitted by law. If
any such term, provision, covenant or remedy of this Agreement or the
application thereof to any person, association, or entity or circumstances
shall, to any extent, be construed to be invalid or unenforceable in whole or
in part, then such term, provision, covenant or remedy shall be construed in a
manner so as to permit its enforceability under the applicable law to the
fullest extent permitted by law. In any case, the remaining provisions of this
Agreement or the application thereof to any person, association or entity or
circumstances other than those to which they have been held invalid or
unenforceable, shall remain in full force and effect.

         8.7. This Agreement shall be binding upon and inure to the benefit of
Company and any other person, association or entity which may hereafter acquire
or succeed to all or substantially all of the business or assets of Company by
any means whether direct or indirect, by purchase, merger, consolidation or
otherwise. Company may assign this Agreement to any Affiliate or any other
entity of NATCO Group Inc. Employee's rights and obligations under this
Agreement hereof are personal and such rights, benefits, and obligations of
Employee shall not be voluntarily or involuntarily assigned, alienated, or
transferred, whether by operation of law or otherwise, without the prior
written consent of Company.

         8.8. There exist other agreements between Company and Employee
relating to the employment relationship between them, e.g., the agreement with
respect to Company policies contained in Company's Business Ethics Policies and
agreements with respect to indemnification and incentive matters. This
Agreement replaces and merges previous agreements and discussions pertaining to
the following subject matters covered herein: the nature of Employee's
employment relationship with Company and the term and termination of such
relationship. This Agreement constitutes the entire agreement of the parties
with regard to such subject matters, and contains all of the covenants,
promises, representations, warranties and agreements between the parties with
respect such subject matters. Each party to this Agreement acknowledges that no
representation, inducement, promise or agreement, oral or written, has been
made by either party with respect to such subject matters, which is not
embodied herein, and that no agreement, statement or promise relating to the
employment of Employee by Company that is not contained in this Agreement shall
be valid or binding. Any modification of this Agreement will be effective only
if it is in writing and signed by each party whose rights hereunder are
affected thereby, provided that any such modification must be authorized or
approved by the Board of Directors of Company.


IN WITNESS WHEREOF, Company and Employee have duly executed this Agreement in
multiple originals to be effective on the date first stated above.

NATCO GROUP INC.



By:
   ------------------------------------------
     George K. Hickox, Jr.
     Chairman of the Governance, Nominating &
       Compensation Committee of the
       NATCO Group Inc. Board of Directors

This 10th day of December 2004

JOHN U. CLARKE


---------------------------------------------

This 10th day of December 2004


                                                                             10

<PAGE>


                                   EXHIBIT A
                       TO EXECUTIVE EMPLOYMENT AGREEMENT
                  BETWEEN NATCO GROUP INC. AND JOHN U. CLARKE

Employee Name:                      John U. Clarke

Term:                               Approximately three years (expires
                                    December 31, 2007)

Position:                           Chairman of the Board of Directors and Chief
                                    Executive Officer of NATCO Group Inc.;
                                    Chief Executive Officer of National Tank
                                    Company

Reporting Relationship:             NATCO Group Inc. Board of Directors

Location:                           Houston, Texas

Annual Base Salary:                 Employee's annual base salary shall not be
                                    less than $396,000.

Bonus:                              Employee will be eligible to participate in
                                    the 2005 NATCO Group Inc. Annual Bonus Plan
                                    or any appropriate replacement bonus plan
                                    of Company or National Tank Company. All
                                    bonuses are discretionary and shall be paid
                                    in accordance with the terms and provisions
                                    of the applicable plan. The annual targeted
                                    incentive is 75% of the annual base salary.

                                    In consideration of Employee's service as
                                    interim CEO and acceptance of a permanent
                                    position with Company, Employee shall
                                    receive a one-time bonus payment of
                                    $100,000 on January 10, 2005.

Long Term Incentives:
                                    o   57,000 shares of non-performance based
                                        restricted stock, with restrictions
                                        lapsing after 3 years of service,
                                        subject to earlier lapse on Change of
                                        Control, death or disability, grant
                                        date January 5, 2005
                                    o   22,000 shares of performance based
                                        restricted stock, with restrictions
                                        lapsing upon achievement of $1.00 EPS as
                                        provided in, and having terms similar
                                        to, 9/9/04 grants to other senior
                                        officers, grant date December 7, 2004
                                    o   Nonqualified Stock Options to acquire
                                        up to 39,500 shares having terms
                                        similar to 9/9/04 grants to other
                                        senior officers, grant date December 7,
                                        2004
                                        43,000 shares of performance based
                                    o   restricted stock, with restrictions
                                        lapsing after the Company's stock has
                                        traded @ $12.00/share or more for 30
                                        consecutive trading days, expiring
                                        after 5 years if restrictions do
                                        not lapse prior to such time, grant
                                        date January 5, 2005
                                    o   Employee is eligible to participate in
                                        any long-term incentive plans as
                                        recommended and approved by the Board
                                        of Directors of NATCO Group Inc. In the
                                        event of a Change of Control as defined
                                        in Article 3, Section 3.6(e),
                                        accelerated vesting shall occur on the
                                        Change of Control date for all unvested
                                        options under any award grants that
                                        have not otherwise expired.

Vacation Benefits:                  Employee shall receive four weeks of
                                    vacation per year accrued on a bi-weekly
                                    basis.

Permitted Activities:               Authorized to continue to participate on
                                    Board of Director assignments with Houston
                                    Exploration Company, Harvest Natural
                                    Resources, Inc. and FuelQuest, provided that
                                    there are no conflicts of interest as
                                    determined by the NATCO Group Inc. Audit
                                    Committee.