Abstract: A Healthcare Funding Exchange (“HFX”) is implemented as a business service domain of service components communicating with each other wherein the execution of a complete interaction with an external actor is effected by the combined performance of executions by the service components. Each component can operate independently of all the others, and can be accessed by the others through service requests conveyed by a service broker. A complete interaction with an actor external to the domain occurs by one component performing its role, providing a service response, and potentially also issuing new service requests to other components, either during or at the end of its own processing. The service components in a business service domain also all have access to data they may share. One component generally has the responsibility for changing any given element of the shared data, but any components may read it.