In traditional haggling ("position-based" bargaining), the parties begin by stating their respective positions. As negotiations progress, the parties give ground only gradually, while trying to wear down the other side with hard bargaining tactics, e.g., threatening to walk out. If an agreement is reached at all, it will be the product of concessions under pressure, and the experience may poison the ongoing relationship between the parties.

A different approach is "interest-based" bargaining, where the parties, instead of taking and defending extreme positions, sit side-by-side and list the issues to be decided. Then they try to work together to explore creative ways to resolve the listed issues. An illustration of the two methods is the dispute over an orange, between two parties named Alpha and Bravo.

In "position-based" bargaining, Alpha claims ownership of the orange, citing favorable arguments and facts [e.g., that Alpha paid for the orange, suggested buying the orange, etc.]. Bravo cites contrary arguments and facts [e.g., Bravo selected the orange, stored the orange, etc.]. Each party will try to discredit the other party's arguments, if not the other party's credibility.

The available alternatives for resolution by position-based bargaining are limited:

Consequently, one party, and maybe both parties, are dissatisfied, and their ongoing relationship has been damaged by the pressure tactics employed during the process

In "Interest-based" bargaining, Alpha and Bravo sit side-by-side and list the aspects and components of the orange, and then brainstorm to come up with ideas. Maybe it turns out that Alpha is primarily interested in the orange rind, to make a cake, while Bravo wants the juice of the orange, and the seeds may be useful to one or both and therefore are divided accordingly. By proceeding in this way, an agreement can be reached by which both parties get most of what they want, and their relationship is undamaged.

Interest-based negotiation was developed by the Harvard Project on Negotiation and popularized in the 1981 best-selling book [which is still in print and well worth reading] "Getting to Yes: Negotiating Agreement Without Giving In", by Roger Fisher and William Ury, Penguin Books.

The Harvard Project model aims to preserve relationships, and produce a "wise"agreement [an agreement that meets legitimate concerns, resolves conflicts, is durable, and is obtained at a minimal cost]. Comparing some of the Harvard Project concepts to mediation of a divorce might look like the following.

Harvard Project: "Deal directly with the people problem"

Harvard Project: "Focus on interests, not positions"

An example might be if one spouse says "I want the house," the mediator might recommend listing all of the issues underlying that position, such as:

Harvard Project: "Develop multiple options"

Continuing the above example, the spouses could then discuss these and other underlying issues, to decide whether to sell the house and move to two smaller homes in the same area, or for one spouse to keep the house for a specified period, or to keep it indefinitely, or some other resolution. The result would depend on what issues are most important to the spouses, and what practical ways can be worked out to best serve those interests.

Harvard Project: "Gather and organize information"

Harvard Project: "Proceed independent of trust"

Harvard Project: "Use independent criteria"

Harvard Project: Produce a "wise agreement."

Thus, following the above mediation divorce procedures will facilitate producing a "wise" Marital Settlement Agreement which resolves all the issues with a minimum of cost, delay, and rancor, and with a much better chance of keeping an amicable relationship for future cooperation.