Event handlers enable a running business process to react to events that might be triggered by a partner. By definition, events occur independently and asynchronously. There may be zero or MULTIPLE events at any time.

Event handlers can be associated with either a scope or with the business process (Start activity i.e global scope). When a scope starts, all associated event handlers are enabled. The event handlers belonging to a scope are disabled when the scope ends. If the scope ends with a fault, the processing of the event handler is terminated.

There are two types of events:

1. INCOMING messages that correspond to a WSDL operation. A STATUS query or a cancellation is common examples of such events. A correlation MUST be specified for the incoming messages. 
2. Alarms that go off after a user-defined period of time, or when a predefined point in time is reached. You can specify ALARM events to repeat after a specified period of time.

Event handlers enable a running business process to react to events that might be triggered by a partner. By definition, events occur independently and asynchronously. There may be zero or multiple events at any time.

Event handlers can be associated with either a scope or with the business process (Start activity i.e global scope). When a scope starts, all associated event handlers are enabled. The event handlers belonging to a scope are disabled when the scope ends. If the scope ends with a fault, the processing of the event handler is terminated.

There are two types of events: