Negotiation mechanisms have been studied widely in the ?eld of multi-agent systems. They possess a variety of features that enable agents be negotiate with each other even in open environments. However, mainly because of l- ited computational power, there are several assumptions that traditionally limit the degree of openness. Recent studies have tended to focus on c- pletely open and highly uncertain environments that apply agent systems to the real world. For example, in emergency rescue domains, we cannot expect to know when and where a ?re starts and when humans are likely to be - jured. Also, in Internet auctions, there can be shill bids since there are many unauthenticated participants. Nowadays, we can employ machines with large computational power to compute an optimal way for agents to negotiate, even incompletelyopenandhighlyuncertainenvironments. Forthepracticaluseof multi-agent systems in the real world, the reliability of each agentβs behavior is essentially required. Concretely, agents must obtain the most appropriate solution/solutions based on rational, robust, and secure negotiation among multiple agents even if the environment is intractable. We solicit papers on all aspects of such negotiation mechanisms in multi-agent systems, including multi-issue negotiations, concurrent negotiations, strategy-proof mechanisms, rational argumentation, auctions and voting, and so on. These issues are - ing explored by researchers from di?erent communities in multi-agent s- tems. They are, for instance, being studied in agent negotiation, multi-issue negotiations, auctions, mechanism design, electronic commerce, voting, - cure protocols, matchmaking and brokering, argumentation, and co-operation mechanisms.