Rather than listening attentively to the opponent, parties may instead be planning their own response, or listening to their own constituency. Finally, even when parties are both listening and talking to each other, misunderstandings and misinterpretations may occur. Fisher, Ury and Patton suggest techniques for minimizing communication problems. Negotiating about interests means negotiating about things that people really want and need, not what they say that want or need. Often, these are not the same.
People tend to take extreme positions that are designed to counter their opponents' positions.
This means negotiators should look for new solutions to the problem that will allow both sides to win, not just fight over the original positions which assume that for one side to win, the other side must lose. The fourth rule is to insist on objective criteria for decisions. While not always available, if some outside, objective criteria for fairness can be found, this can greatly simplify the negotiation process. If union and management are struggling over a contract, they can look to see what other similar companies have agreed to use as an outside objective criteria. If people are negotiating over the price of a car or a house, they can look at what similar houses or cars have sold for.