Process execution (process brokering) involves the execution of discrete steps (tasks) within a business process. A business process engine (BPE) is required to manage the finite state of a business process.

The BPE is at the core of a process execution environment. It is responsible for moving the right work item to the right person at the right time. Thus, the BPE provides flow control over the business process. If a process step has failed or is delayed, compensating actions can be enacted as an alternative process execution branch. This compensating action may be as simple as an e-mail notification, or it may invoke another process to perform corrective action.

At process execution time, there are many causes that require on-the-fly changes of process instances. Dynamic binding and releasing of process elements, such as subprocesses and activities, is required. Also, users may decline work items assigned to them, reassign work items, or accept work items originally not assigned to them. These features are well received by users that participate in less structured processes, such as knowledge workers. They require the capability to adapt processes to their dynamic needs, in essence modifying them at will.