The following press release provides insight on industry trends and behaviors impacting all players involved in clinical research as analyzed and reported by CenterWatch.

FOR IMMEDIATE RELEASE

washingtonpost.com, Newsweek.com and CenterWatch to Increase Awareness of Medical Research with Launch of Clinical Trials Center

--New advertorial section on washingtonpost.com and Newsweek.com informs and connects patients with clinical trials across the U.S.--

Arlington, VA - July 12, 2004 - washingtonpost.com, Newsweek.com and Thomson CenterWatch today announced their collaboration on the Clinical Trials Center. This new advertorial section, hosted on washingtonpost.com and Newsweek.MSNBC.com, is the first of its kind among major news sites.

The Clinical Trials Center is intended to provide a new online resource for those interested in participating in trials. Faced with limited budgets and competing research, clinical trial organizations are looking for new ways to recruit patient volunteers. The lack of patient volunteers remains the single largest obstacle to bringing new therapies to market. The combination benefit of an advertorial center and a targeted advertising campaign on both news sites will allow individual trials to reach the largest possible audience.

"We are excited to work with CenterWatch on this online resource," said Steve Stup, vice president of sales at Washingtonpost.Newseek Interactive. "The Clinical Trial Center is a great example of the power of the Web, bringing the latest medical research opportunities to the people who need it most, the patients."

The Clinical Trial Center is a featured advertorial section and will be accessible via the respective Health Sections of washingtonpost.com and Newsweek.com. There are three sponsored sub-sections; Frequently Asked Questions, Recruiting This Week, and a customized state-by-state paid listing of trials from CenterWatch.

"Of the people who would consider getting involved in clinical research, 74% say they don't know where studies are conducted or how to evaluate them." said Dan McDonald, vice president for Thomson CenterWatch. "Through the Clinical Trials Center, we are taking an important step forward in building awareness about clinical trials."

About Washingtonpost.Newsweek Interactive
Washingtonpost.Newsweek Interactive is the online publishing subsidiary of The Washington Post Company (NYSE:WPO). Its mission is to develop the company's editorial products and businesses on the Internet and across all electronic content delivery platforms. WPNI's flagship products include washingtonpost.com and Newsweek.MSNBC.com. The company is headquartered in Arlington, VA.

About The Thomson Corporation and CenterWatch
The Thomson Corporation (www.thomson.com), with 2003 revenues from continuing operations of $7.6 billion, is a global leader in providing integrated information solutions to business and professional customers in the fields of healthcare and scientific research, law, tax, accounting, financial services, higher education, reference information, corporate training and testing and assessment. Its healthcare solutions include CenterWatch (www.centerwatch.com), a leader in the clinical trials industry. With a specific focus on the clinical trials industry, CenterWatch is a Boston-based publishing and information services company that provides business journalism, reference databases, accredited training manuals, original research and analysis, and market intelligence services to assist organizations in managing and implementing clinical research strategies and operational initiatives. The Thomson Corporation's common shares are listed on the Toronto and New York stock exchanges (TSX: TOC - News; NYSE: TOC - News).

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