Getting to Yes, Negotiating Agreement Without Giving In · Roger Fisher and William Ury (Houghton Mifflin 1981) · Harvard Negotiation Project; excellent and short classic, primarily focused on business negotiation; explains interest based negotiation.
Getting Past No, Negotiating Your Way from Confrontation to Cooperation · William Ury (Bantam Books 1991) · Sequel to above, good advice on dealing with difficult people.
Nonviolent Communication: A Language of Life Marshall B. Rosenberg. This book partners practical communication and emotional literacy skills with a powerful vocabulary to help you strengthen relationships, build trust, prevent conflicts and heal emotional pain.
The Empathy Factor Marie Miyashiro. Miyashiro offers a practical framework for empathy in the workplace.
From Conflict to Connection: Transforming Difficult Conversations into Peaceful Resolutions John Kinyon and Ike Lasaster. Learn to have difficult conversations with ease and create agreements that work.
Difficult Conversations, How to Discuss What Matters Most · Douglas Stone, Bruce Patton, Sheila Heen (Penguin 1999) · Great book, easy to read, lots of good examples from everyday life.
The Dynamics of Conflict Resolution, A Practitioner’s Guide Bernie Mayer.