-By Brian Morrissey

NEW YORK WPP Group and Yahoo! have agreed to create an ad buying platform linking the holding company's shops to Yahoo!'s Right Media Exchange.

The multi-year agreement uses WPP's 24/7 Real Media technology to enable WPP shops to more easily target and buy media across Yahoo!, its affiliated sites and the 24/7 Real Media ad network. GroupM, which includes Mediaedge:cia and MindShare, is the first WPP company to begin using the marketplace.

"The way Yahoo! offered to build something and co-develop it with us is interesting to us," said WPP Digital CEO Mark Read. "That's what they brought to the table."

Right Media is Yahoo!'s online ad exchange, matching buyers and sellers of Web inventory. The deal will enable WPP agencies to create a performance-based network, in much the same way as aQuantive built DrivePM. Read said WPP plans to use the platform on behalf of clients, rather than trade on its own.

The deal illustrates the closer collaboration needed between agencies and providers of technology platforms, Read said. WPP rival Publicis in March unveiled a partnership with Google to make the planning, buying and measuring of digital media easier.

WPP has eyed Google warily in the past. Its executives publicly supported the recent bid by Microsoft to acquire Yahoo! to act as a counterweight to Google. Yet Read said WPP, which is one of Google's largest customers, was not looking to create a separate tie with a rival. Instead, he painted the partnership more in terms of WPP's evolution from a collection of media and creative agencies to an organization with a technology offering that can link up with other platforms.

"There's a blurring of the boundaries," he said. "There's an integration of technology into the holding companies and cooperation between the various players."

Yahoo! has hinged its strategy as an independent company on developing a platform called Amp to make the buying and selling of online media easier. It is betting it can combine its publisher experience, ad network assets and tech know-how to compete with the wide-ranging platforms offered by Google and Microsoft.

"As marketers look for new and more efficient ways to reach their customers, we need to help power that," said Michael Walrath, svp of the advertising marketplaces group at Yahoo!.

The deal is non-exclusive, and Walrath said Yahoo! would like to partner with other agencies and agency groups.

The agreement comes as Yahoo! continues to deal with the fallout from Microsoft's $44 billion offer to buy the company. Investor Carl Icahn has bought up the company's shares and developed an alternate slate of directors to pressure the company into reopening negotiations with Microsoft.