Credible negotiation statements and coherent plans

Criteria are developed to determine which negotiation statements are credible with respect to a reference payoff allocation for the negotiator's possible types. An attractive reference allocation is any limit of reference allocations that admit no credible statements. A coherent plan is a negotiation statement that all types can make with likelihood one that is credible with respect to an attractive reference allocation. Coherent plans are shown to exist. Semicoherent plans are also defined, without reference allocations. Sequentially coherent plans are defined for multistage games with no simultaneous moves. Other negotiation structures are considered, including mechanism design by an informed principal.