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                                                                    EXHIBIT 99.1




SVG ANNOUNCES LOWER REVENUE GUIDANCE AND ADDITIONAL COST REDUCTION MEASURES

San Jose, CA, May 14, 2001--Silicon Valley Group announced today that as part of
its plan to further react to the slowdown in the industry, it would reduce
headcount over the next few months by approximately 400 people. This reduction
in force equates to approximately 10% of the Company's work force at March 30,
2001 and will affect its worldwide contract and permanent employees. In addition
to the previously announced five day shut down in the June quarter, the Company
will shut down operations during the weeks of July 2nd and September 4th, 2001.
During these periods, the Company will continue to maintain its customer support
requirements and expects that critical R&D projects will not be impacted during
these periods.

The Company has received additional requests from customers to delay shipment of
product scheduled to be delivered in the current June quarter for its
non-lithography sectors. These delays have prompted the Company to revise the
June quarter's revenue guidance of a 15% to 25% reduction from the March ended
quarter previously given in the earnings release of April 25, 2001. The Company
now believes revenue for the June 30, 2001 quarter could decline 30% to 40% from
the previous quarter's revenue of $209 million.



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"SVG is acting in a responsible way to size the Company to current industry
demand," said Papken Der Torossian, Chairman and CEO. "During these difficult
times the Company will focus on new products and internal efficiencies to
position SVG to take advantage of the eventual recovery."

ABOUT SILICON VALLEY GROUP, INC.: SVG is a leading manufacturer of automated
wafer processing equipment for the worldwide semiconductor industry. The Company
designs, manufactures, and markets technically sophisticated equipment used in
the fabrication of integrated circuits. Its products include photoresist
processing equipment; oxidation, diffusion and low-pressure chemical vapor
deposition processing systems; atmospheric pressure chemical vapor deposition
systems; photolithography exposure tools that use step-and-scan technology; and
precision optical components and systems. Silicon Valley Group is listed on the
NASDAQ Stock Market under the symbol SVGI. The Company's World Wide Web address
is http://www.svg.com.

On October 2, 2000, SVG announced that it had entered into an Agreement and Plan
of Merger with ASM Lithography, Inc. ("ASML"). The Company's stockholders
approved the merger with ASML on February 7, 2001 and the Company expects to
complete the transaction prior to June 1, 2001. Completion of the transaction is
subject to customary closing conditions. In connection with the proposed
transaction, ASML has filed a registration statement on Form F -- 4 and SVG has
filed a proxy statement -- prospectus, each with the Securities and Exchange
Commission. Investors and security holders are advised to read the registration
statement and the proxy statement -- prospectus because they contain important
information. Investors and security holders may obtain a free copy of the proxy
statement -- prospectus and other documents filed by SVG with the Securities and
Exchange Commission at the Securities and Exchange Commission's web site at
http://www.sec.gov. Free copies of the registration statement and other
documents filed by ASML with the SEC may be obtained from ASML by directing a
request to ASML, Attention: Franki D'Hoore (+31 40) 268-3938. Free copies of
the proxy statement -- prospectus and other documents filed by SVG with the SEC
may also be obtained from SVG by directing a request to SVG, Attention: Manager
of Investor Relations (408) 467-5870.

"Safe Harbor" Statement under the U.S. Private Securities Litigation Reform Act
of 1995:

This press release contains certain "forward -- looking" statements within the
meaning of the Private Securities Litigation Reform Act of 1995. These
statements are based on management's current expectations and are naturally
subject to uncertainty and changes in circumstances. Actual results may vary
materially from the expectations contained herein. The forward -- looking
statements contained herein include statements about the Company's expected
financial results in the current quarter, the ability of the Company to support
research and development projects and the expected completion of the pending
merger between ASML and SVG.



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Factors that could cause actual results to differ materially from those
described herein include: orders and sales during the last days of the quarter;
accounting entries and adjustments at the closing of the quarter; changes in
accounting policies and in particular early adoption of Securities and Exchange
Commission Staff Accounting Bulletin 101; the Company's ability to successfully
develop new products; product demand; competition; currency fluctuations; the
economic environment of the semiconductor industry; the general economic
environment; and, with respect to the merger in particular, actions of the U.S.,
foreign and local governments; the inability to successfully integrate the
businesses of ASML and SVG; costs related to the merger; and labor integration
issues. More detailed information about these factors and other factors
affecting ASML and SVG is set forth in the reports filed by ASML and SVG with
the Securities and Exchange Commission. Neither ASML nor SVG is under any
obligation to (and expressly disclaims any such obligation to) update or alter
its forward -- looking statements, whether as a result of new information,
future events or otherwise.







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