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Dynamic, contextual choice: to be made dynamically from the repertoire at
runtime by considering the specific context of the executing instance
Dynamic process evolution: allow the repertoire to be dynamically extended at
runtime, thus providing support for unexpected process deviations, not only for
the current instance, but also for other current and future instantiations of the
process model, leading to natural process evolution
Thus, to accommodate flexibility, such a system would provide each task of a
process instance with the ability to be linked to an extensible repertoire of actions,
one of which to be contextually and dynamically chosen at runtime to carry out the
task. To accommodate exception handling, such a system would provide an exten-
sible repertoire of exception-handling processes to each process instance, members
of which to be contextually and dynamically chosen to handle exceptions as they
occur.
To support dynamic workflow, the Worklet Service presents the repertoire-
member selection actions as worklets. In effect, a worklet is a small, self-contained,
complete workflow process, which handles one specific task (action) in a larger,
1
composite process (activity). A top-level or parent process model is developed
that describes the workflow at a macro level. From that manager process, worklets
may be contextually selected and invoked from the repertoire of each enabled task,
using an associated extensible set of selection rules, when the task instance becomes
enabled during execution. New worklets for handling a task may be added to the
repertoire at any time (even during process execution) as different approaches to
completing a task are developed and derived from the context of each process
instance. Importantly,the new worklet becomes an implicit part of the process model
for all current and future instantiations, avoiding issues of migration and version
control. In this way, the process model undergoes a dynamic natural evolution.
The worklet approach provides support for the modeling, analysis, and enactment
of business processes, and directly provides for dynamic exception handling, ad-hoc
change, and process evolution, without having to resort to off-system intervention
and/or system downtime.

4.5 Context, Rules, and Worklet Selection

For any situation, there are multiple situational and personal factors that combine to
influence a choice of action. The set of factors that are deemed to be relevant to the
current situation we call its context.
The consideration of context plays a crucial role in many diverse domains,
including philosophy, pragmatics, semantics, cognitive psychology, and artificial
intelligence. Capturing situated context involves quantifying and recording the

1
In Activity Theory terms, a worklet may represent one action within an activity, or may represent
an entire activity.