Online juggernauts in the consumer space, Yahoo! and WebMD announced today that they have inked an exclusive multi-year search and advertising distribution agreement. Financial terms of the deal were not disclosed.

Under the pact, Yahoo! will power search-based and image-heavy display to WebMD consumer advertising sites, which include WebMD health, MedicineNet, eMedicine Health and RxList. WebMD will also be able to show ads sold by its own sales force to visitors of its sites who later go to Yahoo! sites, the companies said.

“This strategic agreement dramatically extends WebMD’s ability to uniquely reach health-involved consumers across the breadth of both WebMD and Yahoo! properties,” said WebMD president and CEO Wayne Gattinella, in a statement.

Todd Teresi, SVP of the Yahoo! Publisher Network, added, “This agreement ushers in a new era of collaboration and value creation for marketers seeking qualified audiences, consumers demanding relevant experiences and for our collective organizations as we look to build upon our unique strengths.”