An automated agent that has to act in a multi-agent environment needs the capability to negotiate. In this paper we concentrate on problems that arise while evaluating suggestions during negotiations. We distinguish between different kind of suggestions and present methods and techniques for evaluating them. The suggestions are written using a formal Negotiation Language that we have developed. W e show how our approach was successfully implemented in a specific environment: the Diplomacy game.As in other board games, playing Diplomacy involves a certain amount of technical skill but the capacity to negotiate, explain, convince, promise, keep promises or choose not to keep them, is an essential ingredient of good play. Diplomat was evaluated and consistently played better than well experienced players, and in games that were held,many players did not guess which player Diplomat was playing.

This paper reports on the development of a Decision Support System GENIE that aids participants in crisis negotiation simulations. GENIE is an instance of a general DSS which can be used to support a large class of decision problems. The major function of GENIE is to provide the user with on-line information about a complex decision scenario. To this end, GENIE utilizes a combination of graphic and textual information presentation formats to create an environment in which a user can develop a mental picture of the decision problem facing him/her and then dynamically formulate an effective negotiating strategy. The design and development of GENIE are described along with an explanation of the major features of the system. Experimental results from user evaluations and system log files are also discussed. These results allowed us to gain insight into the decision processes of the users and rate the effectiveness of our DSS design strategy. Experimental results indicate that simulation participants who had access to the system performed on average better than participants without access to the system.