Title: Searching for Joint Gains in Multi-Party Negotiations

Authors: Harri Ehtamo, Eero Kettunen and Raimo P. Hämäläinen

Status: European Journal of Operational Research, Vol. 130, No. 1, February 2001, pp. 54-69.

Keywords: Negotiation support; Multicriteria analysis; Multi-party; Coordination; Group decision.

We develop a constructive approach to multi-party negotiations over continuous issues. The method is intended to be used as a mediator's tool for step by step creation of joint gains in order to reach a Pareto-optimal agreement. During the mediation process the parties are only required to answer relatively simple questions concering their preferences; they do not have to reveal their utility functions completely. The method generates jointly improving directions to move along, and it is a non-trivial generalization of the recently proposed two-party methods. We give a mathematical analysis together with a numerical example, but also a practical basis for negotiation support in real-world settings.