The articles Getting smart about supply chain management" and "Building enduring consortia" argue that the performance of business-to-business (B2B) e-marketplaces has been disappointing because they haven’t focused on collecting and distributing information from and about their participants. Yet for the participants, the articles observe, it is no easy matter to derive long-term value from better information.

To ascertain the perceptions of the people who actually use and run B2B marketplaces, McKinsey surveyed hundreds of companies in the third quarter of the year 2000 (see sidebar, "About the research"). Among other things, the survey sought to answer these questions: How much and what kind of value do B2B e-marketplaces offer? Is it long-term value? If it doesn’t come from sharing information, what is its source?

Our work shows that buyers, investors, and marketplace executives each define value differently. Certainly, for buyers to obtain real long-term value from a marketplace, it has to do more than merely cut suppliers’ margins; to be successful, it must offer information and capabilities that its customers can use throughout the purchasing process.

In general, marketplaces perform either of two functions: undertaking a particular purchasing activity for customers or giving...