Let me begin that I wouldn't look to trade Zambrano first. However, Zambrano is a FA after this year. If the Cubs can't get him signed to an extension, and if the Cubs aren't competing for a WS this season, it would be best to trade him rather than letting him walk for nothing. I would approach him and offer him an Oswalt-like extension. If he turns that down, it's pretty apparent nothing is going to get done. At that point I'd entertain offers. I'd look for one major-league ready player, one top level prospect, and a couple of projects. I might even try to use him in a three-way deal that would net the Cubs a player like Cabrera, who is young, productive, and would be under team control longer than Zambrano.