They said in a release the enhanced collaboration will feature more games between the two leagues and "broadening the national scope of both conferences."
The two have met in the Rose Bowl game in Pasadena, Calif., 62 times, including 55 consecutive meetings from 1947-2001, and now are seeking more games against each other in all sports, the two league commissioners said.
In football, the new arrangement will mean 12 inter-conference games annually between the two conferences by the 2017 season, with plans calling for each school to play an opponent from the other conference every year.
As far as an annual preseason game, Pac-12 Commissioner Larry Scott told the Los Angeles Times it's in the cards, possibly by 2013 or 2014.
"The Rose Bowl is interested, both conferences are interested," Scott said. "There are no details yet, but it's fair to say you'll see it in some form or fashion."