STAMFORD, Connecticut, September 27 /PRNewswire/ --

- Acquisition to Expand Thomson Scientific's Market-leading Portfolio of 
Chemistry and Drug Discovery Information Solutions

The Thomson Corporation (NYSE: TOC; TSX: TOC), a leading provider of 
information solutions to business and professional customers worldwide, today 
announced that it has acquired Prous Science, a global leader in the 
provision of life sciences information solutions. Prous Science will become 
part of Thomson Scientific. Financial terms of the transaction were not 
disclosed.

Scientists worldwide rely on Prous Science information solutions to
enhance knowledge-based drug discovery and development. Its well-known Prous
Science Integrity(R) portal provides access to more than 265,000 compounds
with demonstrated biological activity and close to 100,000 patent family
records. Prous Science has worked closely with its customers and partners to
develop this highly differentiated information offering tailored to the needs
of end user scientists.

In addition, Prous Science has developed strong relationships with key
global medical associations and Centers of Excellence to maximize the reach
of medical knowledge to specialists worldwide.

"Prous Science has built a strong global brand on its flagship solutions
which have been built by scientists for scientists," said Vin Caraher,
President and CEO, Thomson Scientific. "This acquisition really complements
our Pharma & Biotechnology workflow solution offerings. We look forward to
working closely with the Prous Science management team to maximize synergies
and add value for our customers."

"Today's announcement signals an excellent opportunity to accelerate our
product development and innovation plan in the drug discovery space. By
combining the financial strength, creativity and technology of Thomson with
Prous Science, we will further drive innovations that help scientists find
better solutions to their specific problems while fostering the emergence of
new ideas," said Dr. J.R. Prous, President and CEO, Prous Science.

Headquartered in Barcelona, Spain, where the company's operations will
remain, Prous Science serves key strategic geographic areas including Europe,
Japan, North America and Latin America. Founded in 1958 by current President
and CEO Dr. J.R. Prous, the company has more than 180 employees. Prous
Science management and employees will become part of the
Pharmaceutical/Chemical business unit within Thomson Scientific.

"Thomson Scientific, through its core products, including Thomson Pharma,
IDDB, Derwent World Patents Index and Web of Science, has particular
strengths in patent, business intelligence and investigational drug
information," said Jon Brett-Harris, Executive Vice President of Pharma/Chem
Markets, Thomson Scientific. "The Prous Integrity platform complements our
portfolio offering by providing unparalleled drug discovery content and
unique analytic functionality for chemists and biologists."

"Our strong background in the life sciences coupled with Thomson
Scientific's expertise in intellectual property and competitive intelligence
equal a powerful value proposition for customers of both companies," added
Dr. Josep Prous Jr., Executive Vice President, Prous Science.

The Thomson Corporation

The Thomson Corporation ( http://www.thomson.com ) is a global leader in
providing essential electronic workflow solutions to business and
professional customers. With operational headquarters in Stamford, Conn.,
Thomson provides value-added information, software tools and applications to
professionals in the fields of law, tax, accounting, financial services,
scientific research and healthcare. The Corporation's common shares are
listed on the New York and Toronto stock exchanges (NYSE: TOC; TSX: TOC).

Thomson Scientific is a business of The Thomson Corporation. Its
information solutions assist professionals at every stage of research and
development-from discovery to analysis to product development and
distribution. Thomson Scientific information solutions can be found at
http://www.scientific.thomson.com .

About Prous Science

For more than 40 years, Prous Science has been a trusted source of
information on which science depends to discover safer and more effective
medicines. The company's products have evolved through the years from print
journals to sophisticated electronic products incorporating the latest
advances in IT. The company has complemented its Drug discovery solutions
with a series of key partnerships to widen the dissemination of Medical
Education worldwide by fostering relationships with key Medical Institutions
and centers of excellence worldwide. For more information about Prous
Science, visit http://www.prous.com .

This news release includes forward-looking statements which are based on
certain assumptions and reflect The Thomson Corporation's current
expectations. All forward-looking statements in this news release are subject
to a number of risks and uncertainties that could cause actual results or
events to differ materially from current expectations. Some of the factors
that could cause actual results to differ materially from current
expectations include risks related to Thomson Scientific's ability to
successfully integrate Prous Science, and actions of Thomson Scientific's
competitors. Additional factors are discussed in the Corporation's materials
filed with the securities regulatory authorities in Canada and the United
States from time to time, including the Corporation's latest annual
information form, which is contained in its most recently filed annual report
on Form 40-F. The Corporation disclaims any intention or obligation to update
or revise any forward-looking statements, whether as a result of new
information, future events or otherwise, other than as required by law.

Web site: http://www.thomson.com
              http://www.prous.com
              http://www.scientific.thomson.com