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                                                                     EXHIBIT 1.1



                                4,786,178 SHARES

                             CORE LABORATORIES N.V.

                                  COMMON SHARES


                             UNDERWRITING AGREEMENT


                                                                    May __, 2000


CREDIT SUISSE FIRST BOSTON CORPORATION
SALOMON SMITH BARNEY INC.
DEUTSCHE BANC ALEX. BROWN
CIBC WORLD MARKETS CORP.
DAIN RAUSCHER INCORPORATED
MORGAN KEEGAN & COMPANY, INC.,
  As Representatives of the Several Underwriters,
    c/o Credit Suisse First Boston Corporation,
                    Eleven Madison Avenue,
                    New York, NY 10010-3629


Dear Sirs:

         1. Introductory. The stockholders listed in Schedule A hereto ("SELLING
STOCKHOLDERS") propose severally to sell an aggregate of 4,786,178 outstanding
shares ("FIRM SECURITIES") of the common shares, NLG 0.03 par value per share
("COMMON SHARES") of Core Laboratories N.V., a Netherlands Naamloze Vennootschap
("COMPANY"), and the Company also proposes to sell to the Underwriters, at the
option of the Underwriters, an aggregate of not more than 717,927 additional
outstanding shares ("OPTIONAL SECURITIES") of the Company's Securities as set
forth below. The Firm Securities and the Optional Securities are herein
collectively called the "OFFERED SECURITIES". The Selling Stockholders and First
Britannia Mezzanine N.V., a Netherlands Naamloze Vennootschap ("FIRST BRITANNIA
MEZZANINE N.V."), hereby agree with the Company and with the several
Underwriters named in Schedule B hereto ("UNDERWRITERS") as follows:


         2. Representations and Warranties of the Company and the Selling
Stockholders.

         (a) The Company represents and warrants to, and agrees with, the
several Underwriters that:

                  (i) A registration statement on Form S-3 (No. 333-36042)
         relating to the Offered Securities, including a form of prospectus, has
         been filed with the Securities and Exchange Commission ("COMMISSION")
         and either (A) has been declared effective under the Securities Act of
         1933 ("ACT") and is not proposed to be amended or (B) is proposed to be
         amended by amendment or post-effective amendment. If such registration
         statement (the "INITIAL REGISTRATION STATEMENT") has been declared
         effective, either (A) an additional registration statement (the
         "ADDITIONAL REGISTRATION STATEMENT") relating to the Offered Securities
         may have been filed with the Commission pursuant to Rule 462(b) ("RULE
         462(B)") under the Act and, if so filed, has become effective upon
         filing pursuant to such Rule and the Offered Securities all have been
         duly registered under the Act pursuant to the initial registration
         statement and, if applicable, the additional registration statement or
         (B) such an additional registration statement is proposed to be filed
         with the Commission pursuant to Rule 462(b) and will become effective
         upon filing pursuant to such Rule and upon such filing the Offered
         Securities will all have been duly registered under the Act pursuant to
         the initial registration statement and such additional registration
         statement. If the Company does not propose


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         to amend the initial registration statement or if an additional
         registration statement has been filed and the Company does not propose
         to amend it, and if any post-effective amendment to either such
         registration statement has been filed with the Commission prior to the
         execution and delivery of this Agreement, the most recent amendment (if
         any) to each such registration statement has been declared effective by
         the Commission or has become effective upon filing pursuant to Rule
         462(c) ("RULE 462(C)") under the Act or, in the case of the additional
         registration statement, Rule 462(b). For purposes of this Agreement,
         "EFFECTIVE TIME" with respect to the initial registration statement or,
         if filed prior to the execution and delivery of this Agreement, the
         additional registration statement means (A) if the Company has advised
         the Representatives that it does not propose to amend such registration
         statement, the date and time as of which such registration statement,
         or the most recent post-effective amendment thereto (if any) filed
         prior to the execution and delivery of this Agreement, was declared
         effective by the Commission or has become effective upon filing
         pursuant to Rule 462(c), or (B) if the Company has advised the
         Representatives that it proposes to file an amendment or post-effective
         amendment to such registration statement, the date and time as of which
         such registration statement, as amended by such amendment or
         post-effective amendment, as the case may be, is declared effective by
         the Commission. If an additional registration statement has not been
         filed prior to the execution and delivery of this Agreement but the
         Company has advised the Representatives that it proposes to file one,
         "EFFECTIVE TIME" with respect to such additional registration statement
         means the date and time as of which such registration statement is
         filed and become effective pursuant to Rule 462(b). "EFFECTIVE DATE"
         with respect to the initial registration statement or the additional
         registration statement (if any) means the date of the Effective Time
         thereof. The initial registration statement, as amended at its
         Effective Time, including all material incorporated by reference
         therein, including all information contained in the additional
         registration statement (if any) and deemed to be a part of the initial
         registration statement as of the Effective Time of the additional
         registration statement pursuant to the General Instructions of the Form
         on which it is filed and including all information (if any) deemed to
         be a part of the initial registration statement as of its Effective
         Time pursuant to Rule 430A(b) ("RULE 430A(B)") under the Act, is
         hereinafter referred to as the "INITIAL REGISTRATION STATEMENT". The
         additional registration statement, as amended at its Effective Time,
         including the contents of the initial registration statement
         incorporated by reference therein and including all information (if
         any) deemed to be a part of the additional registration statement as of
         its Effective Time pursuant to Rule 430A(b), is hereinafter referred to
         as the "ADDITIONAL REGISTRATION STATEMENT". The Initial Registration
         Statement and the Additional Registration Statement are hereinafter
         referred to collectively as the "REGISTRATION STATEMENTS" and
         individually as a "REGISTRATION STATEMENT". The form of prospectus
         relating to the Offered Securities, as first filed with the Commission
         pursuant to and in accordance with Rule 424(b) ("RULE 424(B)") under
         the Act or (if no such filing is required) as included in a
         Registration Statement, including all material incorporated by
         reference in such prospectus, is hereinafter referred to as the
         "PROSPECTUS". No document has been or will be prepared or distributed
         in reliance on Rule 434 under the Act.

                  (ii) If the Effective Time of the Initial Registration
         Statement is prior to the execution and delivery of this Agreement: (A)
         on the Effective Date of the Initial Registration Statement, the
         Initial Registration Statement conformed in all material respects to
         the requirements of the Act and the rules and regulations of the
         Commission ("RULES AND REGULATIONS") and did not include any untrue
         statement of a material fact or omit to state any material fact
         required to be stated therein or necessary to make the statements
         therein not misleading, (B) on the Effective Date of the Additional
         Registration Statement (if any), each Registration Statement conformed,
         or will conform, in all material respects to the requirements of the
         Act and the Rules and Regulations and did not include, or will not
         include, any untrue statement of a material fact and did not omit, or
         will not omit, to state any material fact required to be stated therein
         or necessary to make the statements therein not misleading, and (C) on
         the date of this Agreement, the Initial Registration Statement and, if
         the Effective Time of the Additional Registration Statement is prior to
         the execution and delivery of this Agreement, the Additional
         Registration Statement each conforms, and at the time of filing of the
         Prospectus pursuant to Rule 424(b) or (if no such filing is required)
         at the Effective Date of the Additional Registration Statement in which
         the Prospectus is included, each Registration Statement and the
         Prospectus will conform, in all material respects to the requirements
         of the Act and the Rules and Regulations, and neither of such documents
         includes, or will include, any untrue statement of a material fact or
         omits, or will omit, to state any material fact required to be stated
         therein or necessary to make the statements therein not misleading. If
         the Effective Time of the Initial Registration Statement is subsequent
         to the execution and delivery of this Agreement: on the Effective Date
         of the Initial Registration Statement, the Initial


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         Registration Statement and the Prospectus will conform in all material
         respects to the requirements of the Act and the Rules and Regulations,
         neither of such documents will include any untrue statement of a
         material fact or will omit to state any material fact required to be
         stated therein or necessary to make the statements therein not
         misleading, and no Additional Registration Statement has been or will
         be filed. The two preceding sentences do not apply to statements in or
         omissions from a Registration Statement or the Prospectus based upon
         written information furnished to the Company by the Selling
         Stockholders specifically for use therein, or by any Underwriter
         through the Representatives specifically for use therein, it being
         understood and agreed that the only information furnished by the
         Underwriters is that described as such in Section 7(c) hereof.

                  (iii) The Commission has not issued an order preventing or
         suspending the use of the Prospectus relating to the Offered Securities
         nor instituted proceedings for that purpose.

                  (iv) The documents incorporated by reference in the
         Registration Statement and the Prospectus, at the time filed with the
         Commission, or to the extent such documents were subsequently amended
         prior to the date hereof, at the time so amended, conformed in all
         material respects to the requirements of the Securities Exchange Act of
         1934, as amended (the "Exchange Act"), and the rules and regulations of
         the Commission thereunder, or the Act and the Rules and Regulations, as
         applicable.

                  (v) There are no contracts or other documents that are
         required by the Act or by the Rules and Regulations to be filed as
         exhibits to the Registration Statement or to documents incorporated by
         reference into the Registration Statement that have not been so filed.
         The description in the Prospectus of material contracts and other
         documents is accurate in all material respects; to the knowledge of the
         Company, all material contracts described in or filed as exhibits to
         the Registration Statement are in full force and effect on the date
         hereof and are enforceable by the Company in accordance with their
         respective terms; and neither the Company nor any of its subsidiaries,
         nor, to the Company's knowledge, any other party, is in breach of or
         default under any such material contracts.

                  (vi) The Company has been duly incorporated and is an existing
         Naamloze Vennootschap in good standing under the laws of the
         Netherlands, with corporate power and authority to own its properties
         and conduct its business as described in the Prospectus; and the
         Company is duly qualified to do business as a foreign corporation in
         good standing in all other jurisdictions in which its ownership or
         lease of property or the conduct of its business requires such
         qualification, except where the failure to so qualify would not have a
         material adverse effect on the condition (financial or other),
         business, properties, rights or results of operations of the Company
         and its subsidiaries taken as a whole ("MATERIAL ADVERSE EFFECT").

                  (vii) Each Significant Subsidiary of the Company has been duly
         incorporated and is an existing corporation in good standing under the
         laws of the jurisdiction of its incorporation, with corporate power and
         authority to own its properties and conduct its business as described
         in the Prospectus; and each Significant Subsidiary of the Company is
         duly qualified to do business as a foreign corporation in good standing
         in all other jurisdictions in which its ownership or lease of property
         or the conduct of its business requires such qualification, except
         where the failure to so qualify would not have a Material Adverse
         Effect; all of the issued and outstanding capital stock of each
         Significant Subsidiary of the Company has been duly authorized and
         validly issued and is fully paid and nonassessable; and the capital
         stock of each Significant Subsidiary owned by the Company, directly or
         through subsidiaries, is owned free from liens, encumbrances and
         defects, except to the extent pledged under that certain Amended and
         Restated Credit Agreement among Core Laboratories N.V., Core
         Laboratories, Inc., Core Laboratories (U.K.) Limited, Bankers Trust
         Company, NationsBank, N.A. and the Bank Group dated July 18, 1997, as
         amended by Amendment to Amended and Restated Credit Agreement effective
         as of July 23, 1999. Exhibit A hereto is a list of all of the
         "significant subsidiaries" (as such term is defined in the Rules and
         Regulations) of the Company and such significant subsidiaries are
         referred to herein as the "Significant Subsidiaries".

                  (viii) The Firm Securities and all other outstanding shares of
         capital stock of the Company have been, and the Optional Securities
         when issued and sold pursuant hereto will be, duly authorized and
         validly issued, fully paid and nonassessable and conform to the
         description thereof contained in the Prospectus; and the stockholders
         of the Company have no preemptive rights with respect to the Offered
         Securities.


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                  (ix) There are no outstanding securities of the Company
         convertible or exchangeable into or evidencing the right to purchase or
         subscribe for any shares of capital stock of the Company and there are
         no outstanding or authorized options, warrants or rights of any
         character obligating the Company to issue any shares of its capital
         stock (except with respect to outstanding options issued pursuant to
         the Company's employee and non-employee director stock option plans) or
         any securities convertible or exchangeable into or evidencing the right
         to purchase or subscribe for any shares of such stock. In connection
         with this offering, the Company has not offered and will not offer its
         Common Shares, or any other securities convertible into or exchangeable
         or exercisable for Common Shares in a manner in violation of the Act.
         The Company has not distributed and will not distribute any offering
         material other than the Prospectus in connection with the offer and
         sale of the Offered Securities.

                  (x) Except as disclosed in the Prospectus, there are no
         contracts, agreements or understandings between the Company and any
         person that would give rise to a valid claim against the Company or any
         Underwriter for a brokerage commission, finder's fee or other like
         payment in connection with the sale of the Offered Securities.

                  (xi) There are no contracts, agreements or understandings
         between the Company and any person granting such person the right to
         require the Company to file a registration statement under the Act with
         respect to any securities of the Company owned or to be owned by such
         person or to require the Company to include such securities in the
         securities registered pursuant to the Registration Statement or in any
         securities being registered pursuant to any other registration
         statement filed by the Company under the Act that have not been
         satisfied or waived prior to the date hereof.

                  (xii) The outstanding Common Shares are listed on The New York
         Stock Exchange and the Offered Securities have been approved for
         listing thereon upon official notice of issuance.

                  (xiii) No consent, approval, authorization, or order of, or
         filing with, any governmental agency or body or any court is required
         to be obtained or made by the Company for the consummation of the
         transactions contemplated by this Agreement in connection with the sale
         of the Offered Securities, except such as have been obtained and made
         under the Act and such as may be required under state securities laws.

                  (xiv) The execution, delivery and performance of this
         Agreement, and the consummation of the transactions herein contemplated
         will not result in a breach or violation of any of the terms and
         provisions of, or constitute a default under: (A) any statute, any
         rule, regulation or order of any governmental agency or body or any
         court, domestic or foreign, having jurisdiction over the Company or any
         subsidiary of the Company or any of their properties, (B) any agreement
         or instrument to which the Company or any such subsidiary is a party or
         by which the Company or any such subsidiary is bound or to which any of
         the properties of the Company or any such subsidiary is subject or (C)
         the charter or by-laws, deeds of settlement, memorandum of association,
         articles of association or other organizational documents of the
         Company or any such subsidiary, except that, with respect of such
         breaches, violations or defaults of the type specified in clauses (A)
         and (B) which would not reasonably be expected to have, individually or
         in the aggregate, a Material Adverse Effect.

                  (xv) This Agreement has been duly authorized, executed and
         delivered by the Company.

                  (xvi) Except as disclosed in the Prospectus, the Company and
         its Significant Subsidiaries have good and marketable title to all real
         properties and all other properties and assets owned by them, in each
         case free from liens, encumbrances and defects that would materially
         affect the value thereof or materially interfere with the use made or
         to be made thereof by them; and except as disclosed in the Prospectus,
         the Company and its Significant Subsidiaries hold any leased real or
         personal property under valid and enforceable leases with no exceptions
         that would materially interfere with the use made or to be made thereof
         by them.


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                  (xvii) The Company and its Significant Subsidiaries possess
         adequate certificates, authorities or permits issued by appropriate
         governmental agencies or bodies necessary to conduct the business now
         operated by them and have not received any notice of proceedings
         relating to the revocation or modification of any such certificate,
         authority or permit that would reasonably be expected to have,
         individually or in the aggregate, a Material Adverse Effect.

                  (xviii) The Company and each of its Significant Subsidiaries
         carry, or are covered by, insurance issued by insurers of recognized
         financial responsibility against such losses and risks and in such
         amounts as is customary for companies of comparable size engaged in a
         similar business; and neither the Company nor any such Significant
         Subsidiary has any reason to believe that it will not be able to renew
         its existing coverage as and when such coverage expires or to obtain
         similar coverage from similar insurers as may be necessary to continue
         its business at a cost that would not result in any Material Adverse
         Effect or to prevent the consummation of the transactions contemplated
         hereby.

                  (xix) No labor dispute with the employees of the Company or
         any Significant Subsidiary exists or, to the knowledge of the Company,
         is imminent that would be reasonably expected to have a Material
         Adverse Effect.

                  (xx) The Company and its Significant Subsidiaries own, possess
         or can acquire on reasonable terms, adequate trademarks, trade names
         and other rights to inventions, know-how, patents, copyrights,
         confidential information and other intellectual property (collectively,
         "INTELLECTUAL PROPERTY RIGHTS") necessary to conduct the business now
         operated by them, or presently employed by them, and have not received
         any notice of infringement of or conflict with asserted rights of
         others with respect to any intellectual property rights that would
         reasonably be expected to have, individually or in the aggregate, a
         Material Adverse Effect.

                  (xxi) Except as disclosed in the Prospectus, neither the
         Company nor any of its subsidiaries is in violation of any statute, any
         rule, regulation, decision or order of any governmental agency or body
         or any court, domestic or foreign, relating to the use, disposal or
         release of hazardous or toxic substances or relating to the protection
         or restoration of the environment or human exposure to hazardous or
         toxic substances (collectively, "ENVIRONMENTAL LAWS"), owns or operates
         any real property contaminated with any substance that is subject to
         any environmental laws, is liable for any off-site disposal or
         contamination pursuant to any environmental laws, or is subject to any
         claim relating to any environmental laws, which violation,
         contamination, liability or claim would individually or in the
         aggregate have a Material Adverse Effect; and the Company is not aware
         of any pending investigation which might lead to such a claim.

                  (xxii) Except as disclosed in the Prospectus, there are no
         pending actions, suits or proceedings against or affecting the Company,
         any of its subsidiaries or any of their respective properties that
         would reasonably be expected to have, individually or in the
         aggregate, a Material Adverse Effect, or would materially and adversely
         affect the ability of the Company to perform its obligations under this
         Agreement, or which are otherwise material in the context of the sale
         of the Offered Securities; and no such actions, suits or proceedings
         are, to the Company's knowledge, threatened.

                  (xxiii) The financial statements included in each Registration
         Statement and the Prospectus present fairly the financial position of
         the Company and its consolidated subsidiaries as of the dates shown and
         their results of operations and cash flows for the periods shown, and
         such financial statements have been prepared in conformity with the
         generally accepted accounting principles in the United States applied
         on a consistent basis.

                  (xxiv) Except as disclosed in the Prospectus, since the date
         of the latest audited financial statements included in the Prospectus,
         there has been no material adverse change, nor any development or event
         involving a prospective material adverse change, in the condition
         (financial or other), business, properties or results of operations of
         the Company and its subsidiaries taken as a whole, and, except as


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         disclosed in or contemplated by the Prospectus, there has been no
         dividend or distribution of any kind declared, paid or made by the
         Company on any class of its capital stock.

                  (xxv) The Company and its subsidiaries have filed all federal
         state, local and foreign tax returns that have been required to be
         filed and have paid all taxes indicated by said returns and all
         assessments received by them or any of them to the extent that such
         taxes have become due and are not being contested in good faith and for
         which an adequate reserve for accrual has been established in
         accordance with generally accepted accounting principles and except for
         such taxes the nonpayment of which would not have a Material Adverse
         Effect. All tax liabilities have been adequately provided for in the
         financial statements of the Company, and the Company does not know of
         any actual or proposed additional material tax assessments.

                  (xxvi) Arthur Andersen LLP, who have certified certain of the
         financial statements filed with the Commission and incorporated by
         reference in the Registration Statement, are independent public
         accountants as required by the Act and the Rules and Regulations.

                  (xxvii) The Company has timely filed all reports required to
         be filed under the Act and the Rules and Regulations and the Exchange
         Act and the rules and regulations promulgated thereunder; and all such
         reports, including any amendments or supplements thereto, comply in all
         material respects with the provisions, as appropriate, of the Act and
         the Rules and Regulations or the Exchange Act and the rules and
         regulations promulgated thereunder.

                  (xxviii) The Company is not and, after giving effect to the
         offering and sale of the Offered Securities, will not be an "investment
         company" as defined in the Investment Company Act of 1940.

                  (xxix) To the Company's knowledge, there are no affiliations
         or associations between any member of the NASD and any of the Company's
         officers, directors or 5% or greater securityholders.

                  (xxx) Neither the Company nor any of its Significant
         Subsidiaries nor, to the Company's knowledge, any officer, director or
         employee purporting to act on behalf of the Company or any of its
         Significant Subsidiaries has at any time: (1) made any contributions to
         any candidate for political office, or failed to disclose fully any
         such contributions, in violation of law; or (2) made any payment to any
         state, federal or foreign governmental officer or official or other
         person charged with similar public or quasi-public duties, other than
         payments required or allowed by applicable law and other than has been
         previously disclosed in reports filed under the Act or the Exchange
         Act.

         (b) Each Selling Stockholder severally represents and warrants to, and
agrees with, the several Underwriters, as of the date hereof and as of the First
Closing Date, that:

                  (i) Such Selling Stockholder has and on each Closing Date
         hereinafter mentioned will have valid and unencumbered title to the
         Offered Securities to be delivered by such Selling Stockholder on such
         Closing Date and full right, power and authority to enter into this
         Agreement and the Power of Attorney and Custody Agreement referred to
         below and to sell, assign, transfer and deliver the Offered Securities
         to be delivered by such Selling Stockholder on such Closing Date
         hereunder; and upon the delivery of and payment for the Offered
         Securities on each Closing Date hereunder the several Underwriters will
         acquire valid and unencumbered title to the Offered Securities to be
         delivered by such Selling Stockholder on such Closing Date.

                  (ii) This Agreement and the Power of Attorney and Custody
         Agreement referred to below have been duly authorized, executed and
         delivered by or on behalf of such Selling Stockholder and each
         constitutes a legal, valid and binding agreement of such Selling
         Stockholder and is enforceable in accordance with its terms, except as
         the enforceability thereof may be limited by bankruptcy, insolvency,
         reorganization, fraudulent conveyance, moratorium or similar laws
         relating to or affecting creditors' rights generally and by general
         equitable principles (regardless of whether such enforceability is
         considered in a


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         proceeding in equity or at law) and except as rights to indemnity and
         contribution hereunder and thereunder may be limited under applicable
         law.

                  (iii) If the Effective Time of the Initial Registration
         Statement is prior to the execution and delivery of this Agreement: (A)
         on the Effective Date of the Initial Registration Statement, the
         Initial Registration Statement conformed in all material respects to
         the requirements of the Act and the Rules and Regulations and did not
         include any untrue statement of a material fact or omit to state any
         material fact required to be stated therein or necessary to make the
         statements therein not misleading, (B) on the Effective Date of the
         Additional Registration Statement (if any), each Registration Statement
         conformed, or will conform, in all material respects to the
         requirements of the Act and the Rules and Regulations and did not
         include, or will not include, any untrue statement of a material fact
         and did not omit, or will not omit, to state any material fact required
         to be stated therein or necessary to make the statement therein not
         misleading, and (C) on the date of this Agreement, the Initial
         Registration Statement and, if the Effective Time of the Additional
         Registration Statement is prior to the execution and delivery of this
         Agreement, the Additional Registration Statement each conforms, and at
         the time of filing of the Prospectus pursuant to Rule 424(b) or (if no
         such filing is required) at the Effective Date of the Additional
         Registration Statement in which the Prospectus is included, each
         Registration Statement and the Prospectus will conform, in all material
         respects to the requirements of the Act and the Rules and Regulations,
         and neither of such documents includes, or will include, any untrue
         statement of a material fact or omits, or will omit, to state any
         material fact required to be stated therein or necessary to make the
         statements therein not misleading. If the Effective Time of the Initial
         Registration Statement is subsequent to the execution and delivery of
         this Agreement: on the Effective Date of the Initial Registration
         Statement, the Initial Registration Statement and the Prospectus will
         conform in all material respects to the requirements of the Act and the
         Rules and Regulations, neither of such documents will include any
         untrue statement of a material fact or will omit to state any material
         fact required to be stated therein or necessary to make the statements
         therein not misleading. The two preceding sentences apply only to
         statements in or omissions from a Registration Statement or the
         Prospectus that are based upon written information furnished to the
         Company by such Selling Stockholder specifically for use therein.

                  (iv) Except as disclosed in the Prospectus, there are no
         contracts, agreements or understandings between such Selling
         Stockholder and any person that would give rise to a valid claim
         against the Company or any Underwriter for a brokerage commission,
         finder's fee or other like payment in connection with this offering.

                  (v) Such Selling Stockholder has not taken and will not take,
         directly or indirectly, any action designed to, or that has
         constituted, or that might reasonably be expected to cause or result in
         the stabilization or manipulation of the price of the Common Shares of
         the Company and, other than as permitted by the Act, such Selling
         Stockholder will not distribute any prospectus or other offering
         material in connection with the offering of the Offered Securities.

         3. Purchase, Sale and Delivery of Offered Securities. On the basis of
the representations, warranties and agreements herein contained, but subject to
the terms and conditions herein set forth, each Selling Stockholder agrees,
severally and not jointly, to sell to the Underwriters, and each Underwriter
agrees, severally and not jointly, to purchase from each Selling Stockholder, at
a purchase price of $   per share, that number of Firm Securities (rounded up or
down, as determined by Credit Suisse First Boston Corporation ("CSFBC") in its
discretion, in order to avoid fractions) obtained by multiplying the number of
Firm Securities set forth opposite the name of such Selling Stockholder in
Schedule A hereto by a fraction the numerator of which is the number of Firm
Securities set forth opposite the name of such Underwriter in Schedule B hereto
and the denominator of which is the total number of Firm Securities.

         Certificates in negotiable form for the Offered Securities have been
placed in custody, for delivery under this Agreement, under Custody Agreements
made with various persons acting as custodians ("CUSTODIANS"). Each Selling
Stockholder agrees that the shares represented by the certificates held in
custody for the Selling Stockholders under such Custody Agreements are subject
to the interests of the Underwriters hereunder, that the arrangements made by
the Selling Stockholders for such custody are to that extent irrevocable, and
that the obligations of the Selling Stockholders hereunder shall not be
terminated by operation of law, whether by the death of any individual


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Selling Stockholder or the occurrence of any other event, or in the case of a
trust, by the death of any trustee or trustees or the termination of such trust.
If any individual Selling Stockholder or any such trustee or trustees should
die, or if any other such event should occur, or if any of such trusts should
terminate, before the delivery of the Offered Securities hereunder, certificates
for the Offered Securities shall be delivered by the Custodian of the Offered
Securities of such Selling Stockholder in accordance with the terms and
conditions of this Agreement as if such death or other event or termination had
not occurred, regardless of whether or not the Custodian shall have received
notice of such death or other event or termination.

         The Custodians will deliver the Firm Securities to the Representatives
for the accounts of the Underwriters, at the office of Vinson & Elkins L.L.P.,
2300 First City Tower, 1001 Fannin Street, Houston, Texas, against payment of
the purchase price, subject to Section 5(b)(ii) hereof, in Federal (same day)
funds by official bank check or checks or wire transfer to an account at a bank
acceptable to CSFBC drawn to the order of each of the Selling Stockholders at
the office of Vinson & Elkins L.L.P., at 10:00 A.M., New York time, on May 26,
2000, or at such other time not later than seven full business days thereafter
as CSFBC and the Custodians determine, such time being herein referred to as the
"FIRST CLOSING DATE". The certificates for the Firm Securities so to be
delivered will be in definitive form, in such denominations and registered in
such names as CSFBC requests and will be made available for checking and
packaging at the above office at least 24 hours prior to the First Closing Date.

         In addition, upon written notice from CSFBC given to the Company from
time to time not more than 30 days subsequent to the date of the Prospectus, the
Underwriters may purchase all or less than all of the Optional Securities at the
purchase price per security to be paid for the Firm Securities. The Company
agrees to sell to the Underwriters the respective numbers of Optional Securities
specified in such notice. Such Optional Securities shall be purchased from the
Company for the account of each Underwriter in the same proportion as the number
of Firm Securities set forth opposite such Underwriter's name bears to the total
number of Firm Securities (subject to adjustment by CSFBC to eliminate
fractions) and may be purchased by the Underwriters only for the purpose of
covering over-allotments made in connection with the sale of the Firm
Securities. No Optional Securities shall be sold or delivered unless the Firm
Securities previously have been, or simultaneously are, sold and delivered. The
right to purchase the Optional Securities or any portion thereof may be
exercised from time to time and to the extent not previously exercised may be
surrendered and terminated at any time upon notice by CSFBC to the Company.

         Each time for the delivery of and payment for the Optional Securities,
being herein referred to as an "OPTIONAL CLOSING DATE", which may be the First
Closing Date (the First Closing Date and each Optional Closing Date, if any,
being sometimes referred to as a "CLOSING DATE"), shall be determined by CSFBC
but shall be not later than five full business days after written notice of
election to purchase Optional Securities is given. The Company will deliver the
Optional Securities being purchased on each Optional Closing Date to the
Representatives for the accounts of the several Underwriters, at the office of
Vinson & Elkins L.L.P., against payment of the purchase price in Federal (same
day) funds by official bank check or checks or wire transfer to an account at a
bank acceptable to CSFBC drawn to the order of the Company, at the above office.
The certificates for the Optional Securities being purchased on each Optional
Closing Date will be in definitive form, in such denominations and registered in
such names as CSFBC requests upon reasonable notice prior to such Optional
Closing Date and will be made available for checking and packaging at the above
office at a reasonable time in advance of such Optional Closing Date.

         4. Offering by Underwriters. It is understood that the several
Underwriters propose to offer the Offered Securities for sale to the public as
set forth in the Prospectus.

         5. Certain Agreements of the Company and the Selling Stockholders. (a)
The Company agrees with the several Underwriters and the Selling Stockholders
that:

                  (i) If the Effective Time of the Initial Registration
         Statement is prior to the execution and delivery of this Agreement, the
         Company will file the Prospectus with the Commission pursuant to and in
         accordance with subparagraph (1) (or, if applicable and if consented to
         by CSFBC, subparagraph (4)) of Rule 424(b) not later than the earlier
         of (A) the second business day following the execution and delivery of
         this Agreement or (B) the fifteenth business day after the Effective
         Date of the Initial Registration Statement.


                                       8
   9


         The Company will advise CSFBC promptly of any such filing pursuant to
         Rule 424(b). If the Effective Time of the Initial Registration
         Statement is prior to the execution and delivery of this Agreement and
         an additional registration statement is necessary to register a portion
         of the Offered Securities under the Act but the Effective Time thereof
         has not occurred as of such execution and delivery, the Company will
         file the additional registration statement or, if filed, will file a
         post-effective amendment thereto with the Commission pursuant to and in
         accordance with Rule 462(b) on or prior to 10:00 P.M., New York time,
         on the date of this Agreement or, if earlier, on or prior to the time
         the Prospectus is printed and distributed to any Underwriter, or will
         make such filing at such later date as shall have been consented to by
         CSFBC.

                  (ii) The Company will advise CSFBC promptly of the receipt of
         comments from the Commission, the request of the Commission for any
         amendment or supplement or any other proposal to amend or supplement
         the initial or any additional registration statement as filed or the
         related prospectus or the Initial Registration Statement, the
         Additional Registration Statement (if any) or the Prospectus and will
         not effect such amendment or supplementation without CSFBC's consent;
         and the Company will also advise CSFBC promptly of the effectiveness of
         each Registration Statement (if its Effective Time is subsequent to the
         execution and delivery of this Agreement) and of any amendment or
         supplementation of a Registration Statement or the Prospectus and of
         the institution by the Commission of any stop order proceedings in
         respect of a Registration Statement and will use its best efforts to
         prevent the issuance of any such stop order and to obtain as soon as
         possible its lifting, if issued.

                  (iii) If, at any time when a prospectus relating to the
         Offered Securities is required to be delivered under the Act in
         connection with sales by any Underwriter or dealer, any event occurs as
         a result of which the Prospectus as then amended or supplemented would
         include an untrue statement of a material fact or omit to state any
         material fact necessary to make the statements therein, in the light of
         the circumstances under which they were made, not misleading, or if it
         is necessary at any time to amend the Prospectus to comply with the
         Act, the Company will promptly notify CSFBC of such event and will
         promptly prepare and file with the Commission, at its own expense, an
         amendment or supplement which will correct such statement or omission
         or an amendment which will effect such compliance. Neither CSFBC's
         consent to, nor the Underwriters' delivery of, any such amendment or
         supplement shall constitute a waiver of any of the conditions set forth
         in Section 6.

                  (iv) As soon as practicable, but not later than the
         Availability Date (as defined below), the Company will make generally
         available to its securityholders an earnings statement covering a
         period of at least 12 months beginning after the Effective Date of the
         Initial Registration Statement (or, if later, the Effective Date of the
         Additional Registration Statement) which will satisfy the provisions of
         Section 11(a) of the Act. For the purpose of the preceding sentence,
         "Availability Date" means the 45th day after the end of the fourth
         fiscal quarter following the fiscal quarter that includes such
         Effective Date, except that, if such fourth fiscal quarter is the last
         quarter of the Company's fiscal year, "Availability Date" means the
         90th day after the end of such fourth fiscal quarter.

                  (v) The Company will furnish to the Representatives copies of
         each Registration Statement (seven of which will be signed and will
         include all exhibits), each related preliminary prospectus, and, so
         long as a prospectus relating to the Offered Securities is required to
         be delivered under the Act in connection with sales by any Underwriter
         or dealer, the Prospectus and all amendments and supplements to such
         documents, in each case in such quantities as CSFBC may reasonably
         request. The Prospectus shall be so furnished on or prior to 3:00 P.M.,
         New York time, on the business day following the later of the execution
         and delivery of this Agreement or the Effective Time of the Initial
         Registration Statement. All other such documents shall be so furnished
         as soon as available.

                  (vi) The Company will arrange for the qualification of the
         Offered Securities for sale under the laws of such jurisdictions as
         CSFBC designates and will continue such qualifications in effect so
         long as required for the distribution, except that in no event shall
         the Company be obligated in connection therewith to qualify as a
         foreign corporation or to execute a general consent to service of
         process in any jurisdiction where it is not currently so subject.


                                       9
   10


                  (vii) During the period of one year hereafter, the Company
         will furnish to the Representatives and, upon request, to each of the
         other Underwriters, as soon as practicable after the end of each fiscal
         year, a copy of its annual report to stockholders for such year; and
         the Company will furnish to the Representatives (i) as soon as
         available, a copy of each report and any definitive proxy statement of
         the Company filed with the Commission under the Securities Exchange Act
         of 1934 or mailed to stockholders, and (ii) from time to time, such
         other information concerning the Company as CSFBC may reasonably
         request.

                  (viii) For a period of 90 days after the date of the public
         offering of the Offered Securities, the Company will not offer, sell,
         contract to sell, pledge or otherwise dispose of, directly or
         indirectly, any additional Common Shares or securities convertible into
         or exchangeable or exercisable for any Common Shares, or publicly
         disclose the intention to make any such offer, sale, pledge or
         disposition, without the prior written consent of CSFBC, except grants
         of employee stock options pursuant to the terms of a plan in effect on
         the date hereof, issuances of Common Shares pursuant to the exercise of
         such options or the exercise of any other employee stock options
         outstanding on the date hereof. At or prior to the execution hereof,
         the Company shall have delivered to the Representatives written
         agreements of the persons identified on Exhibit B to the effect that
         for a period of 90 days after the date of the public offering of the
         Offered Securities the persons will not offer, sell, contract to sell
         or otherwise dispose of, directly or indirectly, any shares of capital
         stock of the Company or securities convertible into or exchangeable or
         exercisable for any shares of capital stock of the Company, or publicly
         disclose the intention to make any such offer, sale or disposition, or
         enter into any such transaction, swap, hedge or other arrangement,
         without the prior written consent of CSFBC.

                  (ix) The Company shall not invest, or otherwise use the
         proceeds received by the Company from its sale of the Optional
         Securities in such a manner as would require the Company or any of its
         subsidiaries to register as an investment company under the 1940 Act.

                  (x) The Company will maintain a transfer agent and, if
         necessary under the jurisdiction of organization of the Company, a
         registrar for the Common Shares.

                  (xi) The Company will not take, directly or indirectly, any
         action designed to cause or result in, or that has constituted or might
         reasonably be expected to constitute, the stabilization or manipulation
         of the price of any securities of the Company to facilitate the sale or
         resale of the Offered Securities.

         (b) Each Selling Stockholder agrees with the several Underwriters and
the Company that:

                  (i) First Britannia Mezzanine N.V. will pay all expenses
         incident to the performance of the obligations of it and the
         obligations of the Company (exclusive of indemnity and contribution
         obligations under Section 7 hereof) under this Agreement (including the
         fees and expenses of the Company's accountants and counsel), including
         fees and expenses incurred in connection with the filing of the
         Registration Statement, printing fees and expenses, filing fees and
         other expenses (including fees and disbursements of counsel) incurred
         in connection with qualification of the Offered Securities for sale
         under the laws of such jurisdictions as CSFBC designates and the
         printing of memoranda relating thereto, for any transfer taxes on the
         sale of the Offered Securities by First Britannia Holdings N.V. to the
         Underwriters and for expenses incurred in distributing preliminary
         prospectuses and the Prospectus (including any amendments and
         supplements thereto) to the Underwriters. Each of the Selling
         Stockholders other than First Britannia Holdings N.V. will pay any
         transfer taxes on the sale of the Offered Securities by such Selling
         Stockholder to the Underwriters and the fees and expenses of such
         Selling Stockholder's counsel.

                  (ii) The Selling Stockholders will indemnify and hold harmless
         the Underwriters against any documentary, stamp or similar issue tax,
         including any interest and penalties, on the sale of the Offered
         Securities and on the execution and delivery of this Agreement. All
         payments to be made by the Selling Stockholders hereunder shall be made
         without withholding or deduction for or on account of any present or
         future taxes, duties or governmental charges whatsoever unless the
         Selling Stockholders are compelled by law to deduct or withhold such
         taxes, duties or charges. In that event, the Selling Stockholders shall
         pay such additional amounts as may be necessary in order that the net
         amounts received after such withholding or deduction shall equal the
         amounts that would have been received if no withholding or deduction
         had


                                       10
   11


         been made. First Britannia Mezzanine N.V. and the Selling Stockholders
         agree that any expenses or other amounts payable by First Britannia
         Mezzanine N.V. or a Selling Stockholder to the several Underwriters
         pursuant to subsection (b)(i) or this (b)(ii) may be withheld by the
         several Underwriters from the purchase price otherwise payable to First
         Britannia Holdings N.V. or such other Selling Stockholder,
         respectively.

                  (iii) Each Selling Stockholder agrees to deliver to CSFBC,
         attention: Transactions Advisory Group on or prior to the First Closing
         Date a properly completed and executed United States Treasury
         Department Form W-9 (or other applicable form or statement specified by
         Treasury Department regulations in lieu thereof).

                  (iv) Each Selling Stockholder agrees, for a period of 90 days
         after the date of the public offering of the Offered Securities, not to
         offer, sell, contract to sell, pledge or otherwise dispose of, directly
         or indirectly, any additional shares of the capital stock of the
         Company or securities convertible into or exchangeable or exercisable
         for any shares of such capital stock, or publicly disclose the
         intention to make any such offer, sale or disposition, or enter into
         any such transaction, swap, hedge or other arrangement, without the
         prior written consent of CSFBC.

         6. Conditions of the Obligations of the Underwriters. The obligations
of the several Underwriters to purchase and pay for the Firm Securities on the
First Closing Date and the Optional Securities to be purchased on each Optional
Closing Date will be subject to the accuracy of the representations and
warranties on the part of the Company and the Selling Stockholders herein, to
the accuracy of the statements of Company officers made pursuant to the
provisions hereof, to the performance by the Company and the Selling
Stockholders of their obligations hereunder and to the following additional
conditions precedent:

         (a) The Representatives shall have received a letter, dated the date of
delivery thereof (which, if the Effective Time of the Initial Registration
Statement is prior to the execution and delivery of this Agreement, shall be on
or prior to the date of this Agreement or, if the Effective Time of the Initial
Registration Statement is subsequent to the execution and delivery of this
Agreement, shall be prior to the filing of the amendment or post-effective
amendment to the registration statement to be filed shortly prior to such
Effective Time), of Arthur Andersen LLP confirming that they are independent
public accountants within the meaning of the Act and the applicable published
Rules and Regulations thereunder and stating to the effect that:

                  (i) in their opinion the financial statements examined by them
         and included or incorporated by reference in the Registration
         Statements comply as to form in all material respects with the
         applicable accounting requirements of the Act and the related published
         Rules and Regulations;

                  (ii) to the extent that any of the following information is
         included or incorporated by reference in the Registration Statements,
         on the basis of a reading of the latest available interim financial
         statements of the Company, inquiries of officials of the Company who
         have responsibility for financial and accounting matters and other
         specified procedures, nothing came to their attention that caused them
         to believe that:

                  (A)      the unaudited consolidated net sales, net income and
                           net income per share amounts for the three-month
                           period ended March 31, 2000 included in the
                           Prospectus do not agree with the amounts set forth in
                           the unaudited consolidated financial statements for
                           those same periods or were not determined on a basis
                           substantially consistent with that of the
                           corresponding amounts in the audited statements of
                           income;

                  (B)      at the date of the latest available balance sheet
                           read by such accountants, or at a subsequent
                           specified date not more than three business days
                           prior to the date of such letter, there was any
                           change in the capital stock or any increase in
                           short-term indebtedness or long-term debt of the
                           Company and its consolidated subsidiaries or, at the
                           date of the latest available balance sheet read by
                           such accountants, there was any decrease in
                           consolidated net assets, as compared with amounts
                           shown on the latest balance sheet included in the
                           Prospectus; or


                                       11
   12


                  (C)      for the period from the closing date of the latest
                           income statement included in the Prospectus to the
                           closing date of the latest available income statement
                           read by such accountants there were any decreases, as
                           compared with the corresponding period of the
                           previous year, in consolidated net sales or net
                           operating income in the total or per share amounts of
                           consolidated net income;

         except in all cases set forth in clauses (B) and (C) above for changes,
         increases or decreases which the Prospectus discloses have occurred or
         may occur or which are described in such letter; and

                  (iii) they have compared specified dollar amounts (or
         percentages derived from such dollar amounts) and other financial
         information contained in the Registration Statements (in each case to
         the extent that such dollar amounts, percentages and other financial
         information are derived from the general accounting records of the
         Company and its subsidiaries subject to the internal controls of the
         Company's accounting system or are derived directly from such records
         by analysis or computation) with the results obtained from inquiries, a
         reading of such general accounting records and other procedures
         specified in such letter and have found such dollar amounts,
         percentages and other financial information to be in agreement with
         such results, except as otherwise specified in such letter.

         For purposes of this subsection, (i) if the Effective Time of the
         Initial Registration Statement is subsequent to the execution and
         delivery of this Agreement, "REGISTRATION STATEMENTS" shall mean the
         initial registration statement as proposed to be amended by the
         amendment or post-effective amendment to be filed shortly prior to its
         Effective Time, (ii) if the Effective Time of the Initial Registration
         Statement is prior to the execution and delivery of this Agreement but
         the Effective Time of the Additional Registration Statement is
         subsequent to such execution and delivery, "REGISTRATION Statements"
         shall mean the Initial Registration Statement and the additional
         registration statement as proposed to be filed or as proposed to be
         amended by the post-effective amendment to be filed shortly prior to
         its Effective Time, and (iii) "PROSPECTUS" shall mean the prospectus
         included in the Registration Statements. All financial statements
         included in material incorporated by reference into the Prospectus
         shall be deemed included in the Registration Statements for purposes of
         this subsection.

         (b) If the Effective Time of the Initial Registration Statement is not
prior to the execution and delivery of this Agreement, such Effective Time shall
have occurred not later than 10:00 P.M., New York time, on the date of this
Agreement or such later date as shall have been consented to by CSFBC. If the
Effective Time of the Additional Registration Statement (if any) is not prior to
the execution and delivery of this Agreement, such Effective Time shall have
occurred not later that 10:00 P.M., New York time, on the date of this Agreement
or, if earlier, the time the Prospectus is printed and distributed to any
Underwriter, or shall have occurred at such later date as shall have been
consented to by CSFBC. If the Effective Time of the Initial Registration
Statement is prior to the execution and delivery of this Agreement, the
Prospectus shall have been filed with the Commission in accordance with the
Rules and Regulations and Section 5(a) of this Agreement. Prior to such Closing
Date, no stop order suspending the effectiveness of a Registration Statement
shall have been issued and no proceedings for that purpose shall have been
instituted or, to the knowledge of any Selling Stockholder, the Company or the
Representatives, shall be contemplated by the Commission.

         (c) Subsequent to the execution and delivery of this Agreement, there
shall not have occurred (i) any change, or any development or event involving a
prospective change, in the condition (financial or other), business, properties
or results of operations of the Company or its subsidiaries which, in the
judgment of a majority in interest of the Underwriters including the
Representatives, is material and adverse and makes it impractical or inadvisable
to proceed with completion of the public offering or the sale of and payment for
the Offered Securities; (ii) any downgrading in the rating of any debt
securities of the Company by any "nationally recognized statistical rating
organization" (as defined for purposes of Rule 436(g) under the Act), or any
public announcement that any such organization has under surveillance or review
its rating of any debt securities of the Company (other than an announcement
with positive implications of a possible upgrading, and no implication of a
possible downgrading, of such rating); (iii) any suspension or limitation of
trading in securities generally on the New York Stock Exchange, or any setting
of minimum prices for trading on such exchange, or any suspension of trading of
any securities of the Company on any exchange or in the over-the-counter market;
(iv) any banking moratorium declared by U.S. Federal, New York or Netherlands
authorities; or (v) any outbreak or escalation of major hostilities in which the


                                       12
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United States or other jurisdiction in which the Company has offices is
involved, any declaration of war by Congress or any other substantial national
or international calamity or emergency if, in the judgment of a majority in
interest of the Underwriters including the Representatives, the effect of any
such outbreak, escalation, declaration, calamity or emergency makes it
impractical or inadvisable to proceed with completion of the public offering or
the sale of and payment for the Offered Securities.

         (d) The Representatives shall have received an opinion, dated such
Closing Date (and stating that it may be relied upon by Vinson & Elkins L.L.P.,
counsel to the Company, and Fulbright & Jaworski L.L.P., counsel to the
Underwriters), of Nauta Dutilh, special Netherlands counsel to the Company, to
the effect that:

                  (i) The Company has been duly incorporated and is an existing
         Naamloze Vennootschap in good standing under the laws of the
         Netherlands, with corporate power and authority to own its properties
         and conduct its business as described in the Prospectus; and the
         Company is duly qualified to do business as a foreign corporation in
         good standing in all other jurisdictions in which its ownership or
         lease of property or the conduct of its business requires such
         qualification;

                  (ii) The Offered Securities delivered on such Closing Date and
         all other outstanding shares of the Common Stock of the Company have
         been duly authorized and validly issued, are fully paid and
         nonassessable and conform to the description thereof contained in the
         Prospectus; and the stockholders of the Company have no preemptive
         rights with respect to the Offered Securities;

                  (iii) There are no contracts, agreements or understandings
         known to such counsel between the Company and any person granting such
         person the right to require the Company to file a registration
         statement under the Act with respect to any securities of the Company
         owned or to be owned by such person or to require the Company to
         include such securities in the securities registered pursuant to the
         Registration Statement or in any securities being registered pursuant
         to any other registration statement filed by the Company under the Act
         that have not been waived or satisfied prior to the date hereof;

                  (iv) No consent, approval, authorization or order of, or
         filing with, any governmental agency or body or any court is required
         to be obtained or made by the Company for the consummation of the
         transactions contemplated by this Agreement in connection with the sale
         of the Offered Securities, except such as have been obtained and made
         under the Act and such as may be required under state securities laws;

                  (v) The execution, delivery and performance of this Agreement
         and the consummation of the transactions herein contemplated will not
         result in a breach or violation of any of the terms and provisions of,
         or constitute a default under: (A) any statute, any rule, regulation or
         order of any governmental agency or body or any court having
         jurisdiction over the Company or any Significant Subsidiary of the
         Company or any of their properties, (B) any agreement or instrument to
         which the Company or any such Significant Subsidiary is a party or by
         which the Company or any such Significant Subsidiary is bound or to
         which any of the properties of the Company or any such Significant
         Subsidiary is subject, or (C) the charter or by-laws, deeds of
         settlement, memorandum of association, articles of association or other
         organizational documents of the Company or any such Significant
         Subsidiary, except that, with respect of such breaches, violations or
         defaults of the type specified in clauses (A) and (B) which would not
         reasonably be expected to have, individually or in the aggregate, a
         Material Adverse Effect;

                  (vi) This Agreement has been duly authorized, executed and
         delivered by the Company;

                  (vii) The Optional Securities have been duly and validly
         authorized by the Company for issuance and the Company has full
         corporate power and authority to issue, sell and deliver the Optional
         Securities; and, when the Optional Securities are issued and delivered
         against payment therefor as provided in this Agreement, the Optional
         Securities will have been validly issued and will be fully paid and
         non-assessable, and the issuance of such Optional Securities will not
         be subject to any statutory preemptive rights or similar statutory
         rights or, to such counsel's knowledge, any other preemptive or similar
         rights;


                                       13
   14


                  (viii) The certificates for the Optional Securities are in due
         and proper form under the laws of The Netherlands and the Articles of
         Association of the Company and conform with the form of certificates
         duly authorized by the Board of Supervisory Directors of the Company.
         The form of certificates for the Optional Securities conforms to the
         corporate law of the jurisdiction of the Company's organization and,
         when executed and delivered in definitive form, will be sufficient to
         convey the interest in the Company purported to be evidenced thereby;
         and

                  (ix) Except as described in or contemplated by the Prospectus,
         to the knowledge of such counsel, there are no outstanding securities
         of the Company convertible or exchangeable into or evidencing the right
         to purchase or subscribe for any shares of capital stock of the Company
         and there are no outstanding or authorized options, warrants or rights
         of any character obligating the Company to issue any shares of its
         capital stock or any securities convertible or exchangeable into or
         evidencing the right to purchase or subscribe for any shares of such
         stock; and except as described in the Prospectus, to the knowledge of
         such counsel, no holder of any securities of the Company or any other
         person has the right, contractual or otherwise, that has not been
         satisfied or effectively waived, to cause the Company to sell or
         otherwise issue to them, or to permit them to underwrite the sale of,
         any of the Optional Securities or the right to have any Common Shares
         or other securities of the Company included in the Registration
         Statement or the right, as a result of the filing of the Registration
         Statement, to require registration under the Act of any shares of
         Common Shares or other securities of the Company.

         (e) The Representatives shall have received an opinion, dated such
Closing Date (and stating that it may be relied upon by Fulbright & Jaworski
L.L.P., counsel to the Underwriters), of Vinson & Elkins L.L.P., counsel to the
Company, to the effect that:

                  (i) There are no contracts, agreements or understandings known
         to such counsel between the Company and any person granting such person
         the right to require the Company to file a registration statement under
         the Act with respect to any securities of the Company owned or to be
         owned by such person or to require the Company to include such
         securities in the securities registered pursuant to the Registration
         Statement or in any securities being registered pursuant to any other
         registration statement filed by the Company under the Act that have not
         been waived or satisfied prior to the date hereof;

                  (ii) The Company is not and, after giving effect to the
         offering and sale of the Offered Securities, will not be an "investment
         company" as defined in the Investment Company Act of 1940;

                  (iii) The execution, delivery and performance of this
         Agreement and the consummation of the transactions herein contemplated
         will not result in a breach or violation of any of the terms and
         provisions of, or constitute a default under: (A) any statute, any
         rule, regulation or order of any governmental agency or body of the
         United States, the State of Texas, the State of New York, or the State
         of Delaware applicable to the Company or any Significant Subsidiary,
         any of properties of the Company or any Significant Subsidiary, (B) any
         material agreement or instrument identified as an exhibit to the
         Registration Statement or (C) the charter or by-laws, deeds of
         settlement, memorandum of association, articles of association, or
         other organizational documents of the Company or any Significant
         Subsidiary, except that, with respect of such breaches, violations or
         defaults of the type specified in clauses (A) and (B) which would not
         reasonably be expected to have, individually or in the aggregate, a
         Material Adverse Effect;

                  (iv) The Initial Registration Statement was declared effective
         under the Act as of the date and time specified in such opinion, the
         Additional Registration Statement (if any) was filed and became
         effective under the Act as of the date and time (if determinable)
         specified in such opinion;


                                       14
   15


                  (v) The Prospectus either was filed with the Commission
         pursuant to the subparagraph of Rule 424(b) specified in such opinion
         on the date specified therein or was included in the Initial
         Registration Statement or the Additional Registration Statement (as the
         case may be);

                  (vi) To the knowledge of such counsel, no stop order
         suspending the effectiveness of a Registration Statement or any part
         thereof has been issued and no proceedings for that purpose have been
         instituted or are pending or threatened under the Act;

                  (vii) To such counsel's knowledge, there are no material legal
         or governmental proceeding pending or threatened against the Company
         required to be disclosed in the Registration Statement or the
         Prospectus which are not described as required;

                  (viii) Such counsel is not aware of any contracts or documents
         required to be filed as exhibits to or incorporated by reference in the
         Registration Statement or described in the Registration Statement that
         are not so filed, incorporated by reference or described as required;
         it being understood that such counsel need express no opinion as to the
         financial statements or other financial data contained in the
         Registration Statements or the Prospectus; and

                  (ix) This Agreement has been duly executed and delivered by
         the Company.

                  In addition, nothing has come to the attention of such counsel
that would cause such counsel to believe that each Registration Statement and
the Prospectus, and each amendment or supplement thereto, as of their respective
effective or issue dates, did not appear on its face to comply as to form in all
material respects with the requirements of the Act and the Rules and
Regulations; and such counsel has no reason to believe that any part of a
Registration Statement or any amendment thereto, as of its effective date or as
of such Closing Date, contained any untrue statement of a material fact or
omitted to state any material fact required to be stated therein or necessary to
make the statements therein not misleading or that the Prospectus or any
amendment or supplement thereto, as of its issue date or as of such Closing
Date, contained any untrue statement of a material fact or omitted to state any
material fact necessary in order to make the statements therein, in the light of
the circumstances under which they were made, not misleading (it being
understood that no opinion is given as to the accuracy, completeness or fairness
of the financial statements and supporting schedules and other financial,
accounting or related statistical data included in the Registration Statement or
the exhibits thereto).

         (f) The Representatives shall have received the opinion contemplated in
the Power of Attorney executed and delivered by each Selling Stockholder and
First Britannia Mezzanine N.V. and an opinion, dated such Closing Date, of the
respective counsels of the Selling Stockholders and First Britannia Mezzanine
N.V. (as applicable), to the effect that:

                  (i) Each Selling Stockholder had valid and unencumbered title
         to the Offered Securities delivered by such Selling Stockholder on such
         Closing Date and had full right, power and authority to sell, assign,
         transfer and deliver the Offered Securities delivered by the such
         Selling Stockholder on such Closing Date hereunder; and the several
         Underwriters have acquired valid and unencumbered title to the Offered
         Securities purchased by them from the Selling Stockholders on such
         Closing Date hereunder;

                  (ii) No consent, approval, authorization or order of, or
         filing with, any governmental agency or body or any court is required
         to be obtained or made by any Selling Stockholder for the consummation
         of the transactions contemplated by the Custody Agreement and or this
         Agreement in connection with the sale of the Offered Securities sold by
         the Selling Stockholders, except such as have been obtained and made
         under the Act and such as may be required under state securities laws;

                  (iii) The execution, delivery and performance of the Custody
         Agreement and this Agreement and the consummation of the transactions
         therein and herein contemplated will not result in a breach or
         violation of any of the terms and provisions of, or constitute a
         default under, any statute, any rule, regulation or order of any
         governmental agency or body or any court having jurisdiction over any
         Selling


                                       15
   16



         Stockholder or any of their properties or any agreement or instrument
         to which any Selling Stockholder is a party or by which any Selling
         Stockholder is bound or to which any of the properties of any Selling
         Stockholder is subject, or the charter or by-laws of any Selling
         Stockholder which is a corporation;

                  (iv) The Power of Attorney and related Custody Agreement with
         respect to each Selling Stockholder has been duly authorized, executed
         and delivered by such Selling Stockholder and constitute valid and
         legally binding obligations of each such Selling Stockholder
         enforceable in accordance with their terms, subject to bankruptcy,
         insolvency, fraudulent transfer, reorganization, moratorium and similar
         laws of general applicability relating to or affecting creditors'
         rights and to general equity principles; and

                  (v) This Agreement has been duly authorized, executed and
         delivered by each Selling Stockholder and by First Britannia Mezzanine
         N.V.

         (g) The Representatives shall have received from Fulbright & Jaworski
L.L.P., counsel for the Underwriters, such opinion or opinions, dated such
Closing Date, with respect to the incorporation of the Company, the validity of
the Offered Securities delivered on such Closing Date, the Registration
Statements, the Prospectus and other related matters as the Representatives may
require, and the Selling Stockholders and the Company shall have furnished to
such counsel such documents as they request for the purpose of enabling them to
pass upon such matters. In rendering such opinion, Fulbright & Jaworski L.L.P.
may rely as to the incorporation of the Company and all other matters governed
by Netherlands law upon the opinion of Nauta Dutilh referred to above.

         (h) The Representatives shall have received a certificate, dated such
Closing Date, of the President or any Vice President and a principal financial
or accounting officer of the Company in which such officers, to the best of
their knowledge after reasonable investigation, shall state that: the
representations and warranties of the Company in this Agreement are true and
correct; the Company has complied with all agreements and satisfied all
conditions on its part to be performed or satisfied hereunder at or prior to
such Closing Date; no stop order suspending the effectiveness of any
Registration Statement has been issued and no proceedings for that purpose have
been instituted or are contemplated by the Commission; the Additional
Registration Statement (if any) satisfying the requirements of subparagraphs (1)
and (3) or Rule 462(b) was filed pursuant to Rule 462(b), including payment of
the applicable filing fee in accordance with Rule 111(a) or (b) under the Act,
prior to the time the Prospectus was printed and distributed to any underwriter;
and, subsequent to the dates of the most recent financial statements in the
Prospectus, there has been no material adverse change, nor any development or
event involving a prospective material adverse change, in the condition
(financial or other), business, properties or results of operations of the
Company and its subsidiaries taken as a whole except as set forth in or
contemplated by the Prospectus or as described in such certificate.

         (i) The Representatives shall have received a letter, dated such
Closing Date, of Arthur Andersen LLP which meets the requirements of subsection
(a) of this Section, except that the specified date referred to in such
subsection will be a date not more than three days prior to such Closing Date
for the purposes of this subsection.

         (j) In the event the over-allotment option is exercised, the Optional
Securities shall have been approved for listing on the NYSE.

         (k) The Lockup Agreements described in Section 5(a)(viii) and (b)(iv)
are in full force and effect.

The Selling Stockholders, First Britannia Mezzanine N.V. and the Company will
furnish the Representatives with such conformed copies of such opinions,
certificates, letters and documents as the Representatives reasonably requests.
CSFBC may in its sole discretion waive on behalf of the Underwriters compliance
with any conditions to the obligations of the Underwriters hereunder, whether in
respect of an Optional Closing Date or otherwise.

         7. Indemnification and Contribution.

         (a) The Company will indemnify and hold harmless each Underwriter, its
partners, directors and officers and each person, if any, who controls such
Underwriter within the meaning of Section 15 of the Act, against any losses,
claims, damages or liabilities, joint or several, to which such Underwriter may
become subject, under the Act


                                       16
   17


or otherwise, insofar as such losses, claims, damages or liabilities (or actions
in respect thereof) arise out of or are based upon any untrue statement or
alleged untrue statement of any material fact contained in any Registration
Statement, the Prospectus, or any amendment or supplement thereto, or any
related preliminary prospectus, or arise out of or are based upon the omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, and will
reimburse each Underwriter for any legal or other expenses reasonably incurred
by such Underwriter in connection with investigating or defending any such loss,
claim, damage, liability or action as such expenses are incurred; provided,
however, that the Company will not be liable in any such case to the extent that
any such loss, claim, damage or liability arises out of or is based upon an
untrue statement or alleged untrue statement in or omission or alleged omission
from any of such documents in reliance upon and in conformity with written
information furnished to the Company by any Underwriter through the
Representatives specifically for use therein, it being understood and agreed
that the only such information furnished by any Underwriter consists of the
information described as such in subsection (c) below.

         (b) Each Selling Stockholder, severally and not jointly, will indemnify
and hold harmless each Underwriter, the Company and each other Selling
Stockholder, their respective partners, directors and officers and each person,
if any, who controls such Underwriter or such other Selling Stockholder within
the meaning of Section 15 of the Act, against any losses, claims, damages or
liabilities, joint or several, to which such person may become subject, under
the Act or otherwise, insofar as such losses, claims, damages or liabilities (or
actions in respect thereof) arise out of or are based upon any untrue statement
or alleged untrue statement of any material fact contained in any Registration
Statement, the Prospectus, or any amendment or supplement thereto, or any
related preliminary prospectus, or arise out of or are based upon the omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, and will
reimburse each such person for any legal or other expenses reasonably incurred
by such Underwriter in connection with investigating or defending any such loss,
claim, damage, liability or action as such expenses are incurred; provided,
however, that the Selling Stockholders will be liable in any such case only to
the extent that any such untrue statement or alleged untrue statement or
omission or alleged omission was made in reliance upon and in conformity with
written information furnished to the Company or the Underwriters by such Selling
Stockholder specifically for use therein or arise out of or are based upon any
untrue statement or alleged untrue statement made by such Selling Stockholder in
Section 2(b) of the Agreement.

         (c) Each Underwriter will severally and not jointly indemnify and hold
harmless the Company, its directors and officers and each person, if any, who
controls the Company within the meaning of Section 15 of the Act, each Selling
Stockholder and First Britannia Mezzanine N.V. against any losses, claims,
damages or liabilities to which the Company, such Selling Stockholder or First
Britannia Mezzanine N.V. may become subject, under the Act or otherwise, insofar
as such losses, claims, damages or liabilities (or actions in respect thereof)
arise out of or are based upon any untrue statement or alleged untrue statement
of any material fact contained in any Registration Statement, the Prospectus, or
any amendment or supplement thereto, or any related preliminary prospectus, or
arise out of or are based upon the omission or the alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, in each case to the extent, but only to the
extent, that such untrue statement or alleged untrue statement or omission or
alleged omission was made in reliance upon and in conformity with written
information furnished to the Company by such Underwriter through the
Representatives specifically for use therein, and will reimburse any legal or
other expenses reasonably incurred by the Company, each Selling Stockholder and
First Britannia Mezzanine N.V. in connection with investigating or defending any
such loss, claim, damage, liability or action as such expenses are incurred, it
being understood and agreed that the only such information furnished by any
Underwriter consists of the following information in the Prospectus furnished on
behalf of each Underwriter: the concession and reallowance figures appearing in
the fourth paragraph under the caption "Underwriting".

         (d) Promptly after receipt by an indemnified party under this Section
of notice of the commencement of any action, such indemnified party will, if a
claim in respect thereof is to be made against an indemnifying party under
subsection (a), (b) or (c) above, notify the indemnifying party of the
commencement thereof; but the omission so to notify the indemnifying party will
not relieve it from any liability which it may have to any indemnified party
otherwise than under subsection (a), (b) or (c) above. In case any such action
is brought against any indemnified party and it notifies an indemnifying party
of the commencement thereof, the indemnifying party will be entitled to
participate therein and, to the extent that it may wish, jointly with any other
indemnifying party similarly notified, to assume the defense thereof, with
counsel satisfactory to such indemnified party (who shall not, except with the


                                       17
   18


consent of the indemnified party, be counsel to the indemnifying party), and
after notice from the indemnifying party to such indemnified party of its
election so to assume the defense thereof, the indemnifying party will not be
liable to such indemnified party under this Section for any legal or other
expenses subsequently incurred by such indemnified party in connection with the
defense thereof other than reasonable costs of investigation. No indemnifying
party shall, without the prior written consent of the indemnified party, effect
any settlement of any pending or threatened action in respect of which any
indemnified party is or could have been a party and indemnity could have been
sought hereunder by such indemnified party unless such settlement (i) includes
an unconditional release of such indemnified party from all liability on any
claims that are the subject matter of such action and (ii) does not include a
statement as to, or an admission of, fault, culpability or a failure to act by
or on behalf of an indemnified party.

         (e) If the indemnification provided for in this Section is unavailable
or insufficient to hold harmless an indemnified party under subsection (a), (b)
or (c) above, then each indemnifying party shall contribute to the amount paid
or payable by such indemnified party as a result of the losses, claims, damages
or liabilities referred to in subsection (a), (b) or (c) above (i) in such
proportion as is appropriate to reflect the relative benefits received by the
Company and the Selling Stockholders on the one hand and the Underwriters on the
other from the offering of the Securities or (ii) if the allocation provided by
clause (i) above is not permitted by applicable law, in such proportion as is
appropriate to reflect not only the relative benefits referred to in clause (i)
above but also the relative fault of the Company and the Selling Stockholders on
the one hand and the Underwriters on the other in connection with the statements
or omissions which resulted in such losses, claims, damages or liabilities as
well as any other relevant equitable considerations. The relative benefits
received by the Company and the Selling Stockholders on the one hand and the
Underwriters on the other shall be deemed to be in the same proportion as the
total net proceeds from the offering (before deducting expenses) received by the
Selling Stockholders bear to the total underwriting discounts and commissions
received by the Underwriters. The relative fault shall be determined by
reference to, among other things, whether the untrue or alleged untrue statement
of a material fact or the omission or alleged omission to state a material fact
relates to information supplied by the Company, the Selling Stockholders or the
Underwriters and the parties' relative intent, knowledge, access to information
and opportunity to correct or prevent such untrue statement or omission. The
amount paid by an indemnified party as a result of the losses, claims, damages
or liabilities referred to in the first sentence of this subsection (e) shall be
deemed to include any legal or other expenses reasonably incurred by such
indemnified party in connection with investigating or defending any action or
claim which is the subject of this subsection (e). Notwithstanding the
provisions of this subsection (e), no Underwriter shall be required to
contribute any amount in excess of the amount by which the total price at which
the Securities underwritten by it and distributed to the public were offered to
the public exceeds the amount of any damages which such Underwriter has
otherwise been required to pay by reason of such untrue or alleged untrue
statement or omission or alleged omission. No person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Act) shall be
entitled to contribution from any person who was not guilty of such fraudulent
misrepresentation. The Underwriters' obligations in this subsection (e) to
contribute are several in proportion to their respective underwriting
obligations and not joint.

         (f) The obligations of the Company and the Selling Stockholders under
this Section shall be in addition to any liability which the Company and the
Selling Stockholders may otherwise have and shall extend, upon the same terms
and conditions, to each person, if any, who controls any Underwriter within the
meaning of the Act; and the obligations of the Underwriters under this Section
shall be in addition to any liability which the respective Underwriters may
otherwise have and shall extend, upon the same terms and conditions, to each
director of the Company, to each officer of the Company who has signed a
Registration Statement and to each person, if any, who controls the Company
within the meaning of the Act.

         8. Default of Underwriters. If any Underwriter or Underwriters default
in their obligations to purchase Offered Securities hereunder on either the
First or any Optional Closing Date and the aggregate number of shares of Offered
Securities that such defaulting Underwriter or Underwriters agreed but failed to
purchase does not exceed 10% of the total number of shares of Offered Securities
that the Underwriters are obligated to purchase on such Closing Date, CSFBC may
make arrangements satisfactory to the Selling Stockholders for the purchase of
such Offered Securities by other persons, including any of the Underwriters, but
if no such arrangements are made by such Closing Date, the non-defaulting
Underwriters shall be obligated severally, in proportion to their respective
commitments hereunder, to purchase the Offered Securities that such defaulting
Underwriters agreed but failed to purchase on such Closing Date. If any
Underwriter or Underwriters so default and the aggregate number of shares of


                                       18
   19


Offered Securities with respect to which such default or defaults occur exceeds
10% of the total number of shares of Offered Securities that the Underwriters
are obligated to purchase on such Closing Date and arrangements satisfactory to
CSFBC and the Selling Stockholders for the purchase of such Offered Securities
by other persons are not made within 36 hours after such default, this Agreement
will terminate without liability on the part of any non-defaulting Underwriter,
the Company or the Selling Stockholders, except as provided in Section 9,
(provided that if such default occurs with respect to Optional Securities after
the First Closing Date, this Agreement will not terminate as to the Firm
Securities or any Optional Securities purchased prior to such termination). As
used in this Agreement, the term "Underwriter" includes any person substituted
for an Underwriter under this Section. Nothing herein will relieve a defaulting
Underwriter from liability for its default.

         9. Survival of Certain Representations and Obligations. The respective
indemnities, agreements, representations, warranties and other statements of the
Selling Stockholders, of the Company or its officers and of the several
Underwriters set forth in or made pursuant to this Agreement will remain in full
force and effect, regardless of any investigation, or statement as to the
results thereof, made by or on behalf of any Underwriter, any Selling
Stockholder, the Company or any of their respective representatives, officers or
directors or any controlling person, and will survive delivery of and payment
for the Offered Securities. If this Agreement is terminated pursuant to Section
8 or if for any reason the purchase of the Offered Securities by the
Underwriters is not consummated, the Selling Stockholders shall remain
responsible for the expenses to be paid or reimbursed by them pursuant to
Section 5 and the respective obligations of the Company, the Selling
Stockholders, and the Underwriters pursuant to Section 7 shall remain in effect,
and if any Offered Securities have been purchased hereunder the representations
and warranties in Section 2 and all obligations under Section 5 shall also
remain in effect. If the purchase of the Offered Securities by the Underwriters
is not consummated for any reason other than solely because of the termination
of this Agreement pursuant to Section 8 or the occurrence of any event specified
in clause (iii), (iv) or (v) of Section 6(c), the Selling Stockholders will
jointly and severally, reimburse the Underwriters for all out-of-pocket expenses
(including fees and disbursements of counsel) reasonably incurred by them in
connection with the offering of the Offered Securities.

         10. Certain Agreements of First Britannia Mezzanine N.V. First
Britannia Mezzanine N.V., which is the holder of all of the outstanding capital
stock of First Britannia Holdings N.V., is made a party to this Agreement and
agrees that it is making all representations and warranties and shall be bound
by all covenants and agreements of First Britannia Holdings N.V., specifically
including, without limitation: (i) the representations and warranties set forth
in Section 2(b) hereof, (ii) the reimbursement expenses set forth in Section
5(b)(i) and (ii) hereof and (iii) indemnification and contribution as provided
in Section 7 hereof.

         11. Notices. All communications hereunder will be in writing and, if
sent to the Underwriters, will be mailed, delivered or telegraphed and confirmed
to the Representatives, c/o Credit Suisse First Boston Corporation, Eleven
Madison Avenue, New York, NY 10010-3629, Attention: Investment Banking
Department--Transactions Advisory Group, or, if sent to the Company, will be
mailed, delivered or telegraphed and confirmed to it c/o Core Laboratories,
Inc., 5295 Hollister Road, Houston, Texas 77040, Attention: John D. Denson, or,
if sent to the Selling Stockholders will be mailed, delivered or telegraphed and
confirmed to, each Selling Stockholder at the address set forth on the signature
page hereto; provided, however, that any notice to an Underwriter pursuant to
Section 7 will be mailed, delivered or telegraphed and confirmed to such
Underwriter.

         12. Successors. This Agreement will inure to the benefit of and be
binding upon the parties hereto and their respective personal representatives
and successors and the officers and directors and controlling persons referred
to in Section 7, and no other person will have any right or obligation
hereunder.

         13. Representation. The Representatives will act for the several
Underwriters in connection with the transactions contemplated by this Agreement,
and any action under this Agreement taken by the Representatives jointly or by
CSFBC will be binding upon all the Underwriters. The person indicated as
signatory for each Selling Stockholder on the signature page attached hereto
will act for such Selling Stockholder in connection with such transactions, and
any action under or in respect of this Agreement taken by such person on behalf
of the respective Selling Stockholder will be binding upon such Selling
Stockholder.

         14. Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed to be an original, but all such
counterparts shall together constitute one and the same Agreement.


                                       19
   20


         15. APPLICABLE LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO
PRINCIPLES OF CONFLICTS OF LAWS.

         The Company hereby submits to the non-exclusive jurisdiction of the
Federal and state courts in the Borough of Manhattan in The City of New York in
any suit or proceeding arising out of or relating to this Agreement or the
transactions contemplated hereby.

         The obligation of the Company or any Selling Stockholder in respect of
any sum due to any Underwriter shall, notwithstanding any judgment in a currency
other than United States dollars, not be discharged until the first business
day, following receipt by such Underwriter of any sum adjudged to be so due in
such other currency, on which (and only to the extent that) such Underwriter may
in accordance with normal banking procedures purchase United States dollars with
such other currency; if the United States dollars so purchased are less than the
sum originally due to such Underwriter hereunder, the Company and such Selling
Stockholder agree, as a separate obligation and notwithstanding any such
judgment, to indemnify such Underwriter against such loss. If the United States
dollars so purchased are greater than the sum originally due to such Underwriter
hereunder, such Underwriter agrees to pay to the Company or such Selling
Stockholder an amount equal to the excess of the dollars so purchased over the
sum originally due to such Underwriter hereunder.











                                       20
   21



         If the foregoing is in accordance with the Representatives'
understanding of our agreement, kindly sign and return to the Company one of the
counterparts hereof, whereupon it will become a binding agreement among the
Selling Stockholders, the Company and the several Underwriters in accordance
with its terms.

                                            Very truly yours,

     Address:                               FIRST BRITANNIA MEZZANINE N.V.
     De Ruyterkade 62                       FIRST BRITANNIA HOLDINGS N.V.
     Curacao, Netherlands Antilles

                                            By
                                              ----------------------------------
                                                        Jacobus Shouten,
                                                        Attorney-in-Fact


     Address:                               ROBERT P. ANDREWS
     The Andrews Group International
     1800 Augusta, Suite 200
     Houston, Texas 77057

                                            By
                                              ----------------------------------
                                                      Richard L. Bergmark,
                                                        Attorney-in-Fact


     Address:                               GAS RESEARCH INSTITUTE
     8600 West Bryn Mawr Avenue
     Chicago, Illinois 60631-3562

                                            By
                                              ----------------------------------
                                                      Richard L. Bergmark,
                                                        Attorney-in-Fact


     Address:                               CHRISTOPHER C. PAYTON
     TomoSeis Corporation
     1650 West Sam Houston Parkway North
     Houston, Texas 77043-3115

                                            By
                                              ----------------------------------
                                                      Richard L. Bergmark,
                                                        Attorney-in-Fact


     Address:                               TERRY JBEILI
     TomoSeis Corporation
     1650 West Sam Houston Parkway North
     Houston, Texas 77043-3115

                                            By
                                              ----------------------------------
                                                      Richard L. Bergmark,
                                                        Attorney-in-Fact



                                       21
   22



     Address:                               ESTATE OF PAUL J. CERNOCK
     c/o Thomas Osa Harris                  ESTATE OF ELIZABETH M. CERNOCK
     10405 Town and Country Way
     Suite 211
     Houston, Texas 77024

                                            By
                                              ----------------------------------
                                                       Thomas Osa Harris,
                                                        Attorney-in-Fact


     Address:                               RANDALL S. MILLER
     Reservoirs, Inc.
     1151 Brittmore Road
     Houston, Texas 77043

                                            By
                                              ----------------------------------
                                                      Richard L. Bergmark,
                                                        Attorney-in-Fact

     Address:                               JAMES W. RECTOR, III
     210 Arlington Avenue
     Kensington, California 94707

                                            By
                                              ----------------------------------
                                                      Richard L. Bergmark,
                                                        Attorney-in-Fact


                                            CORE LABORATORIES N.V.


                                            By
                                              ----------------------------------
                                            Name:
                                            Title:

The foregoing Underwriting Agreement is hereby
 confirmed and accepted as of the date first above
 written.

         Acting on behalf of themselves and as the
          Representatives of the several
          Underwriters.


     By  CREDIT SUISSE FIRST BOSTON CORPORATION


     By
       ----------------------------------
     Name:
     Title:

     By  SALOMON SMITH BARNEY INC.


     By
       ----------------------------------
     Name:
     Title:



                                       22
   23



                                   SCHEDULE A




                                                                         NUMBER OF
                                                      NUMBER OF           OPTIONAL
                                                   FIRM SECURITIES       SECURITIES
                    SELLING STOCKHOLDER              TO BE SOLD          TO BE SOLD
                    -------------------           ----------------      -----------
                                                                  
First Britannia Holdings N.V.                              4,202,534            -0-
Robert Andrews                                               350,000            -0-
Gas Research Institute                                        44,390            -0-
Christopher C. Payton                                         42,700            -0-
Terry Jbeili                                                  42,100            -0-
Estate of Paul J. Cernock                                     36,227            -0-
Estate of Elizabeth M. Cernock                                36,227            -0-
Randall S. Miller                                             20,000            -0-
James W. Rector, III                                          12,000            -0-


















                                                        ------------          ------
  Total............................................        4,786,178            -0-
                                                        ============          ======




                                       23
   24


                                   SCHEDULE B




                                                               NUMBER OF
                                                            FIRM SECURITIES
                UNDERWRITER                                 TO BE PURCHASED
                -----------                                 ---------------

                                                      
Credit Suisse First Boston Corporation
Salomon Smith Barney Inc.
Deutsche Banc Alex. Brown
CIBC World Markets Corp.
Dain Rauscher Incorporated
Morgan Keegan & Company, Inc.





                                                            ---------------
          Total......................................             4,786,178
                                                            ===============



                                       24
   25



                                                                       EXHIBIT A


                            SIGNIFICANT SUBSIDIARIES



                            Core Laboratories, Inc.
                            Saybolt International B.V.
                            Saybolt, Inc.
                            ProTechnics Company
                            Core Laboratories International B.V.















                                       25
   26



                                                                       EXHIBIT B


                        ADDITIONAL PERSONS TO ENTER INTO
                                LOCKUP AGREEMENTS


                               Stephen D. Weinroth
                                David M. Demshur
                               Richard L. Bergmark
                                 Joseph R. Perna
                                 John D. Denson
                               Timothy J. Probert
                                  Bob G. Agnew
                                  James A. Read
                                 Monty L. Davis
                                 Randall D. Keys
                                Jacobus Schouten
                                  Rene R. Joyce
                                  D. John Ogren
                             Alexander Vriesendorp


















                                       26