This is an excellent negotiation book. I encourage you to read the book in conjunction with the MOOC that Professor's Siedel created on "Succesful Negotiation: Essential Strategies and Skills" in Coursera. Anyway, the book is a great read and of highly practical use by itself as well.
The book is unique in its organization by covering each step in the negotiation process chronologically from preparation through performance. Accordingly, the book is organized as follows:
Unit I: Prepare to Negotiate Unit II: Use Key Strategies and Tactics During Negotiations Unit III: Close Your Negotiation With a Binding Contract Unit IV: Complete Your End Game Appendix A: Negotiation Planning Checklist Appendix B: Example of a Completed Negotiated Planning Checklist Appendix C: Assess Your Negotiating Style
The chronological order of the book made it easy to understand and each chapter has a "Key takeaway" summarizing the most important concepts covered. Further, the book provides concrete examples and case studies to show how the concepts are applied in practice and is written in a style which provides deep insights through plain language.
I particularly enjoyed the Negotiation Style Assessment and the Chapter on the "Use of Psychological Tools" for negotiation. These set of tools are applicable to many other areas besides negotiation, such as decision making and litigation.