"The need for listening is obvious, yet it is difficult to listen well, especially under the stress of an ongoing negotiation. Listening enables you to understand their perceptions, feel their emotions, and hear what they are trying to say. Active listening improves not only what you hear, but also what they say. If you pay attention and interrupt occasionally to say, 'Did I understand correctly that you are saying that . . . ?' the other side will realize that they are not just killing time, not just going through a routine. They will also feel the satisfaction of being heard and understood. Standard techniques of good listening are to pay close attention to what is said, to ask the other party to spell out carefully and clearly exactly what they mean, and to request that ideas be repeated if there is any ambiguity or uncertainty. Make it your task while listening not to phrase a response, but to understand them as they see themselves. Take in their perceptions, their needs, and their constraints."
from Getting to Yes: Negotiating Agreement Without Giving In by Roger Fisher and William Ury