1. calculating the total combined value all involved parties receive from making a deal 2. trying to increase this value above and beyond their BATNAs 3. then carving up and sharing this excess
So it's about focusing on specialized synergies and value creation. For a more in-depth read I'd recommend Co-Opetition by Brandenburger and Nalebuff (whose class on Negotiations I just completed): http://www.amazon.com/Co-Opetition-Revolution-Combines-Compe...
Deeply understanding prisoner's dilemma helps explain a lot of office politics. Why are people at software firms more willing to ruffle feathers than at insurance companies? Because their prisoners dilemma games are shorter. How do you make sure that someone doesn't reneg on a deal? Make sure they see the game is longer than just 1.
It's not the be-all end all of strategy, but it's very interesting.
Further reading on coopetition:
http://en.wikipedia.org/wiki/Coopetition
http://www.amazon.com/Co-Opetition-Adam-M-Brandenburger/dp/0...
I hate the word co-opetition, because it's a much deeper topic than "Why can't we all get along?" or "Why can't we manipulate each other into not competing?" That said, it's worth understanding.