Despite the managementese title, it's rather interesting. A more appropriate title would be "Applied Game Theory". The book starts out with two party distributive bargaining (a simple zero-sum games better known as "buying or selling something"), and moves to two-party multiple-issues and eventually moves to multilateral negotiations.
At each stage, there are a good mixture of illustrative and real-world examples. As it builds on a decent game-theoretical framework, the counter-intuitive behaviour, optimal approaches, corner cases etc. are highlighted, and the examples really bring the messages home and stop it being dry and theoretical.
You might have thought this book would be the antithesis to Getting to Yes. In many ways, with its analytic style, it is. However, the theory leaves many questions unanswered. It doesn't give a good answer to how to share the value, whether strategic misrepresentation (lying?) is appropriate, what to do about forming groups in multi-lateral negotiations, etc. So, it does fall back to questions of ethics, which the book discusses openly and with some excellent examples.
Moreover, this book does dwell on the "synergies" and "win-win solutions" that Getting to Yes goes on about. Here, though, it's about moving your agreement closer to the efficient frontier. By the time we get to multi-party, multi-subject agreements, the discussion is quite soft, even if there's good, solid theory underpinning it. In the end, this book and Getting to Yes have plenty of scope for agreement. Recommended.