According to me, the best negotiation policy is : Listen and understand the other party’s issues and point of view.
When you do a good job listening, you not only gain new ideas for creating win/win outcomes but also make your counterpart feel cared for and valued. This also allows you to find out what the other party wants. If you assume that his or her wants and needs are the same as yours, you will have the attitude that only one of you can “win” the negotiation.
Develop options and strategies. Successful people are those who have the greatest number of viable alternatives. Similarly, successful negotiators are those who have the most strategies they can use to turn their options into reality.