Although individual services are considered stateless, compositions often have requirements to maintain state information across the invocation of the composed services. The choreographer of the services is often responsible for the management of state. Alternatively, a component that implements and realizes multiple related services or operations on services may need to maintain state between invocations for performance reasons.

State Management in SOA environment can be considered to fall into three main categories:

• Transaction State - where a service has an open transaction during a conversation with a client.
• Security State - where a security context is held open during a conversation with a client.
• Functional State - where the conversation with a client involves a number of related operations.

For more information see the Guideline: State Management for Services.