It is getting more important to have quick response during the negotiation process due to the very competitive environment. However, in the negotiation process, it is quite often that negotiators do not have enough time to understand the negotiation issue, the available alternatives and their priorities. In addition, negotiators may also have difficulties to catch path of interactions between negotiators, i.e. negotiation dance. These problems may have negative impact on the negotiation results or even break the negotiation. The goal of this research is to help negotiators with clearer picture about the negotiation issues and the interactions between negotiators in order to have better negotiation decisions during the negotiation process. First, the challenges in understanding the negotiation issues and the interactions between negotiators are identified. Then, based on the identified challenges, five negotiation decision support agents are designed. The algorithm of each agent is proposed too. In order to evaluate the effectiveness of the proposed agents, prototypes of two agents have been developed and evaluated through an experiment. The result is positive.