Don't argue over positions. Arguing over positions locks you into those positions, and now you have to save face. It also ignores underlying concerns, splitting differences rather than meeting interests.
The classic mistakes are soft negotiation and hard negotiation.
Soft negotiation is wanting to avoid conflict, making concessions and ending up feeling exploited or bitter or with an agreement that doesn't work.
Hard negotiation is seeing every disagreement as a contest of wills, a battle, taking an extreme position and holding out, deceiving the other party as to your true views, dragging your feet, stonewalling, threatening to walk out and making small concessions only as necessary. Hard negotiation produces an equally hard response, exhausts everyone and harms the relationship.
Principled negotiation means deciding issues on their merits rather than through a haggling process, without tricks, without posturing, looking for mutual gains, and (when your interests conflict) insisting that the result be based on some fair standard independent of the will of either side. A wise agreement meets the interests of both sides, resolves conflicts fairly, is durable, is amicable, and improves the relationship.
Separate the people from the problem. Participants should see themselves as side by side, attacking the problem. Remember that the relationship is more important than the negotiation. Build up trust, understanding, respect and friendship. Arrange it so that the other person saves face. Look out for misunderstandings, and drawing unfounded inferences. When perceptions are inaccurate, educate each other. When emotions run high, vent: talk about them without blaming. Feel free to apologize.
Focus on the underlying interests rather than the positions. The most powerful interests are basic human needs: security, well-being, belonging, and control of one's life. Talk about interests. Be specific. Compromising between positions doesn't generate an agreement that satisfies human needs. Positions taken are usually the most obvious ones. Ask what human need a position is trying to satisfy.
Generate a variety of options before deciding on one. It's hard to come up with solutions when you're under pressure, in the presence of an adversary, have a lot at stake, or are searching for the one right answer. Separate the process of inventing possible solutions from the process of deciding among them. Gather information and think about it. Identify both sides' interests. Of your interests, which are most important? Understand the other's interests, putting yourself in their shoes. Have a brainstorming session. Select the most promising ideas and improve them. Evaluate them, looking for shared interests and mutual gain, and decide among them. Look for the win-win solution.
Insist that the result be based on some objective criteria independent of the naked will of either side. Use some objective standard like market value, expert opinion, custom or law.
(From: Getting to Yes: Negotiating Agreement Without Giving In, by Roger Fisher and William Ury and Bruce Patton, editor, second edition, 1991.)
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