The intersystem coordination apparatus includes: a storage unit configured to store a pattern of a communication protocol between the system and the other system, a protocol definition in which system configurations of these systems and network configurations, a non-functioning requirement which is a unique requirement of a predetermined application for the system to access the other system by using the predetermined application, and a plurality of modules configured to execute the application in accordance with the protocol definition and the non-functioning requirement; an application processing unit configured to execute the predetermined application; and a combination processing unit configured to select a module required to execute processing by the application from the plurality of modules based on the non-functioning requirement and a requirement value required to perform processing between these systems determined based on the communication protocol pattern, the system configuration, and the network configuration included in the protocol definition.