Abstract
Enterprise architecture is concerned with the design of an overall architectural vision for organisations. Service oriented architecture is a design paradigm that supports this vision, as applications are built from services that are composed by business processes. A service is a key element of service oriented architecture and represents technical solutions to business problems. The rules of engagement between services are expressed by service contracts in order to govern the execution of business processes. However, organisations develop services and their respective service contracts quickly, often without much thought to their management and maintenance. Services designed in this manner, do not promote governance. To gain an insight into service contract design, this paper describes the contract-first and the contract-last design approaches. The deficiencies of the contract-last design approach are highlighted. Service contract design requirements are identified, and governance is considered as a design requirement to consider. The paper finally proposes that the contract-first approach to service design should ideally be used to support service governance.