Abstract: Based on the review of service properties for emergencies such as an early order in advance, a short implement time, and lower residual value, an optional contract model of service supply chain for emergencies was presented by introducing optional contracts in the traditional service supply chain for emergencies. First, an optimized order strategy of the supply chain integrator under certain optional contracts was derived by analysis of different interests of the integrator and suppliers. Second, a coordination mechanism of service supply chain for emergencies was suggested on parameters of optional contracts, and the profits of general logistics service supply chain were optimized, which reveals that the integrated decision was much better the individual decision in an optional contract supply chain. Third, it was discussed that the changing principle of demand and option order cause by variation of supplies' price and cost under emergencies. Final, a case study was applied to testify that the optimal order quantity will increase with the increase of probability of emergent events, and it will help make more precise decision when integrator can predict information about emergent events.

Key words: emergent events, emergent service supply chain, optional contract, coordination mechanism, interests of the integrator