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                                                                     Exhibit 4.5
                              EMPLOYMENT AGREEMENT

THE UNDERSIGNED:

1.       ASM LITHOGRAPHY HOLDING NV, located at de Run 1110, Veldhoven, The
         Netherlands; in accordance with article 2: 146 Dutch civil code, hereby
         duly represented by Mr. H. Bodt and Mr. A. Westerlaken respectively the
         Chairman and Secretary of the Supervisory Board of ASM Lithography
         Holding N.V., hereinafter referred to as: "ASML";

and

2.       MR. D. J. DUNN, residing at Millstone House, Mill Lane, Swindon SN1 4HG
         United Kingdom, hereinafter referred to as: "Mr. Dunn".


WHEREAS:

(a)      Mr. Dunn will be appointed by the Supervisory Board of ASML as Member
         of the Board of Management of ASML once, on March 11, 1999, the General
         Meeting of Shareholders of ASML has been informed on the intended
         appointment,

(b)      ASML and Mr. Dunn wish to agree upon the terms and conditions of the
         employment agreement that will govern Mr. Dunn's appointment as Member
         of the Board Management of ASML,

HEREBY AGREE AS FOLLOWS:

1.       TASKS AND DUTIES

1.1      ASML hereby employs Mr. Dunn as Member of the Board Management. As of
         January 1, 2000 Mr. Dunn will hold the position of President & Chief
         Executive Officer. Mr. Dunn hereby accepts such employment, upon the
         terms and conditions as set forth in this agreement.

1.2      Mr. Dunn agrees to devote his best efforts, attention and abilities to
         the business and the affairs of ASML. Mr. Dunn shall, at all times,
         observe the best interests of ASML and its affiliates or group
         companies.

1.3      Except with prior written consent of the supervisory Board of ASML, Mr.
         Dunn shall not undertake any other paid or unpaid duties or activities
         for or on behalf of third parties, or perform these duties or
         activities on his own behalf, during the course of this agreement.
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2.       DURATION OF THE AGREEMENT AND TERMINATION

2.1      This agreement shall be in force for a period of five years. The
         effective date of this agreement is April 1, 1999. During the course of
         this agreement, both ASML and Mr. Dunn may terminate this agreement. A
         notice period of six months shall apply in case ASML terminates and a
         notice period of three months shall apply in case Mr. Dunn terminates.
         Any notice hereunder will be given per the end of a calendar month.

2.2      No later than October 1, 2003, ASML and Mr. Dunn will discuss the
         possibilities and conditions of an extension of the employment
         relationship after April 1, 2004. If agreement on an extension is not
         reached before November 1, 2003, this agreement will end automatically
         on April, 2004.

2.3      In the case ASML terminates this agreement during its initial term of
         five years, Mr. Dunn will be entitled to a severance payment equal to
         the lesser of:

         (a)  the gross base salary as mentioned in article 3.1 for the
              remaining term of this agreement, or

         (b)  two times the gross base annual salary as mentioned in article
              3.1,

         unless such termination takes place for an "urgent cause" in the sense
         of article 7:678 Dutch Civil Code.

2.4      Apart from the severance payment set out in article 2.3, Mr. Dunn shall
         not be entitled to any further payment of severance, damages or the
         like in case of termination of the employment agreement. ASML and Mr.
         Dunn hereby declare that the severance payment set out in article 2.3.
         is a fair, reasonable and sufficient payment in relation to a
         termination of this employment agreement during the course of the
         five-year period.

3.       SALARY

3.1      The gross base salary per year to which Mr. Dunn shall be entitled is
         NLG 1,000 (one million dutch guilders).

         The salary will be paid in 12 equal parts at the end of each calendar
         month. The Supervisory Board will review annually whether, in its
         opinion, an increase in the gross base salary is justified. ASML and
         Mr. Dunn will jointly put forward a request to the dutch tax
         authorities to be able to apply the so called 35% tax ruling.

3.2      Mr. Dunn is not entitled to a separate holiday allowance, as this
         allowance is deemed to be included in the gross base salary.

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3.3      Without prejudice to the reference in article 3.1 related to the
         request for the 35% ruling, the salary payments mentioned in 3.1 shall
         be subject to the usual statutory withholdings, such as tax and social
         security premiums.

3.4      The payments mentioned in this agreement shall be made to a Dutch bank
         account to be indicated by Mr. Dunn.

4.       BONUS/STOCK OPTIONS

4.1      Mr. Dunn is entitled to a yearly bonus up to a maximum of 50% of his
         gross base salary per year. The bonus is determined per year by the
         Supervisory Board and will be related to specific pre set targets and
         the actual results of ASML over such year. The Supervisory Board has
         the authority to amend the bonus system whenever it feels that such
         amendment is required or advisable.

4.2      The bonus referred to in article 4.1 shall be paid by ASML to Mr. Dunn
         within four months after the end of the calendar year.

4.3      Mr. Dunn is not entitled to a bonus as mentioned in article 4.1:

         (a)   that relates to a year during which he was not able to perform
               his duties due to illness for a consecutive period of four months
               or more, or

         (b)   that relates to a year in which he was suspended for any period
               of time.

4.4      Mr. Dunn shall be entitled to 200,000 stock options in ASML upon
         signing of this agreement subject to statutory Dutch tax withholdings.
         Furthermore Mr. Dunn will be eligible to participate in the Management
         Option Program as approved by the Supervisory board of ASML.

5.       CAR/EXPENSES/TRAVEL

5.1      Mr. Dunn is entitled to a company car that shall be leased by ASML. The
         costs of the lease shall be bone by ASML to a maximum of NLG 4,000 per
         month (inclusive of petrol).

5.2      Any reasonable expenses properly incurred by Mr. Dunn in the
         performance of his duty, shall be reimbursed by ASML, in accordance
         with the standard procedure within the organization of ASML. An account
         of such expenses, accompanied by supporting receipts and other
         appropriate evidence, shall be rendered by Mr. Dunn to ASML prior to
         any reimbursement.

5.3      Mr. Dunn and his partner shall be entitled to a maximum of twenty
         return flights a year from Eindhoven or Amsterdam to the UK at the
         expense of ASML for non-business purposes.

5.4      ASML will pay Mr. Dunn an amount of NLG 60,000 as reimbursement for the
         costs of moving - including decorating costs - to The Netherlands at
         the



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         beginning of this employment agreement. ASML will further reimburse the
         reasonable costs of moving back to the UK at the end of this employment
         agreement.

5.5      ASML will reimburse Mr. Dunn the reasonable costs of temporary housing
         near Eindhoven/Veldhoven for a period up to the first eight weeks of
         Mr. Dunn's employment for ASML.

6.       HOLIDAYS

6.1      Mr. Dunn shall be entitled to 30 holidays per year. He is entitled to
         enjoy holidays after consultation with the other members of the Board
         of Management of ASML. Any holidays granted but not taken in one year
         will expire without compensation if not taken in the following two
         years.

7.       ILLNESS OR DISABILITY

7.1      In case of illness or disability of Mr. Dunn, ASML is obliged to pay
         100% of the gross base salary as referred to article 3.1 during the
         first 52 weeks of illness or disability.

7.2      After 52 weeks of illness or disability Mr. Dunn will be entitled to
         payment under the disability insurance
         ('Arbeidsongeschiktheidsverzekering') that ASML has concluded on Mr.
         Dunn's behalf, subject to the terms and conditions of such insurance.
         The costs of such insurance shall be borne by ASML. The disability
         insurance will pay up to 70% of Mr. Dunn's gross base salary, minus any
         other contributions that Mr. Dunn may be entitled to (such as AAW/WAO).

8.       INSURANCE

8.1      Mr. Dunn shall be covered by the ASML travel and accident insurance
         ('Ongevallenverzekering') that will pay up to four times the gross base
         salary per year to Mr. Dunn in case of whole or partial disability of
         Mr. Dunn and up to two times the gross base salary per year to a
         designed party in case of death of Mr. Dunn. The costs of this
         insurance shall be borne by ASML.

8.2      Mr Dunn, his wife and children will be covered by the ASML medical
         insurance ('Ziektekostenverzekering'). Fifty percent of the cost
         thereof shall be borne by ASML and fifty percent by Mr. Dunn.

8.3      Mr. Dunn will be covered by the ASML Director and Officers Liability
         Insurance policy, the costs of which shall be borne by ASML.

9.       PENSION

9.1      Mr. Dunn shall participate in the ASML pension scheme with Aegon.
         Parties will investigate the possibility to transfer any funds that
         have been build up during Mr. Dunn's participation in the pension
         scheme with his former employer (Philips)


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         into the present pension scheme with Aegon. The premium for pension
         scheme will be borne for 60% by ASML and for 40% by Mr. Dunn.

10.      CONFIDENTIALITY AND DELIVERY OF DOCUMENTS

10.1     Mr. Dunn shall, neither during the term of this agreement nor after its
         termination, directly or indirectly use or disclose to any third party
         any information related to the business of ASML, or of any of its group
         companies, which information can be reasonably expected to be secret or
         confidential. The foregoing shall not apply to disclosure or use of
         information with the prior written consent of ASML nor to disclosure
         that is necessary for the adequate performance of Mr. Dunn's duties
         under applicable law.

10.2     Mr. Dunn shall treat all items of ASML, such as books, documents,
         computer floppy disks, other information carriers, resolutions,
         drawings, reports and notes as property of ASML, and he shall treat
         such property with the same degree of care as his own property. Mr.
         Dunn shall not use any item in another way, or keep any item any
         longer, than is necessary for the adequate performance of his duties.
         Mr. Dunn shall deliver all such items to ASML immediately following
         termination of this agreement.

11.      GIFTS/BENEFITS

11.1     In the performance of his duties for ASML, Mr. Dunn shall not accept or
         bargain for any gifts or benefits, in whatever form and however
         defined, from third parties without the prior written consent of ASML.

11.2     Article 11.1 is not applicable to customary non-valuable promotional
         gifts.

12.      NON-COMPETITION

12.1     During the term of this agreement and for a consecutive period of two
         years after its termination, Mr. Dunn shall neither directly nor
         indirectly engage in or be involved in activities in the semiconductor
         lithography equipment manufacturing industry or in activities that are
         otherwise similar or in any way competitive with the activities of
         ASML.

12.2     Mr. Dunn acknowledges that the provisions of this article are
         reasonably necessary to protect the interest of ASML.

13.      PENALTY

13.1     Should Mr. Dunn breach any of the obligations mentioned in article 11
         or 12, ASML shall be entitled to a penalty of NLG 25,000 for every
         breach, to be increased by NLG 5,000 for every day such breach
         continues, without prejudice to any other rights or claims ASML may
         have. The parties hereto acknowledge that the above-mentioned penalty
         represent a genuine and reasonable pre-estimate


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         of the minimum damage likely to be suffered by ASML in case Mr. Dunn
         breaches any of its duties pursuant to article 11 or 12.

13.2     Each of the restrictions in article 11 or 12 shall be independently
         enforceable by ASML.

14.      CODE OF CONDUCT

         Mr. Dunn will be subject to the provisions of the ASML Code of Conduct
         with Respect to Inside Information, in their most recent version.

15.      APPLICABLE LAW

15.1     This agreement shall be governed by the laws of The Netherlands.

15.2     Any disputes arising from this agreement shall be brought before the
         competent court as's-Hertogenbosch, The Netherlands.





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This agreement is signed in twofold on February 23, 1999


/s/ H. Bodt                                /s/ D. J. Dunn
----------------------------------         -------------------------------------
H. Bodt                                    D. J. Dunn
Chairman of the Supervisory Board
of ASM Lithography Holding N.V.



/s/ A. Westerlaken
----------------------------------
A. Westerlaken
Secretary of the Supervisory Board
of ASM Lithography Holding N.V.



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                        AMENDMENT TO EMPLOYMENT AGREEMENT


The undersigned:

1.       ASML Holding N.V., established and headquartered at Veldhoven, the
         Netherlands, represented by H. Bodt and S. Bergsma in their capacity of
         Chairman and member of the Supervisory Board respectively, hereinafter
         referred to as: "ASML";

and

2.       Douglas John Dunn, residing in Pastorij 27, 5508 LT Veldhoven, the
         Netherlands, hereinafter referred to as: "Mr. Dunn";

Hereby agree that as per July 1, 2003 the following shall be an amendment to the
employment agreement between ASM Lithography Holding N.V. and Mr. Dunn dated
February 23, 1999 (the "Employment Agreement"). The remaining provisions of the
Employment Agreement shall be amended as follows:

1.       In this article the following definitions shall apply:

         (a)   "CHANGE OF CONTROL" of ASML means (i) that any merger or
               consolidation of ASML with or into any other individual,
               partnership, company or entity in the broadest sense (hereinafter
               referred to as "Third Party(ies)" or any stock purchase or sale,
               reorganization, recapitalization or other transaction, in each
               case, in one transaction or a series of related transactions, if,
               immediately after giving effect to such transaction(s), any Third
               Party(ies), not currently controlling ASML acquires Control of
               ASML or of its transferee(s) or surviving Third Party(ies) or
               (ii) any sale, transfer or other conveyance, whether direct or
               indirect, of all or substantially all of the assets of ASML, on a
               consolidated basis, in one transaction or a series of related
               transactions;

         (b)   "CONTROL" means, with respect to any Person, the power to
               control, directly or indirectly, greater than 50% of the voting
               interest of such Person, or the ability to appoint or elect more
               than 50% of the Management Board or other equivalent governing
               board of such Person, whether such power is effect through
               ownership of shares or other securities, by contract, by proxy or
               otherwise;

         (c)   "PERSON" means any individual, partnership, limited liability
               company, firm, corporation, company, association, trust,
               unincorporated organization or other entity.

2.       In the event notice of termination of this agreement is given by ASML
         or its legal successor in connection with a Change of Control, the
         rights of the Statutory


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         Director under any of the applicable ASML stock option plan(s) shall
         not be subject to the restrictions contained in the relevant articles
         related to termination of employment in the applicable ASML stock
         option plans and the Statutory Director shall remain entitled to
         exercise options during the full original Option Period as defined in
         those stock option plans. In addition the Statutory Director is not
         subject to any Embargo Period as defined in the applicable ASML stock
         option plan(s) and consequently the Statutory Director can exercise any
         option(s) held by him without being restricted as per the relevant
         articles in the applicable ASML stock option plans. This provision 15.2
         also applies if the Statutory Director gives notice of termination,
         provided that this notice of termination is directly related to the
         Change of Control and such notice is given within 12 months from the
         date on which the Change of Control occurs.

3.       The provisions of this article do not affect any other rights the
         parties have or may have under Dutch law in the event of a termination
         of this agreement.

In witness whereof, this document has been signed and executed in duplicate this
14th day of July 2003.


/s/ H. Bodt                                 /s/ D. J. Dunn
-----------------------------------         ------------------------------------
H. Bodt                                     D. J. Dunn
Chairman of the Supervisory Board
of ASM Lithography Holding N.V.



/s/ S. Bergsma
-----------------------------------
S. Bergsma
Member of the Supervisory Board
of ASML Holding N.V.





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