The 20 workflow patterns proposed by van der Aalst et al. provide a comprehensive benchmark for comparing
process modelling languages. In this article, we discuss workflow pattern support of Event-Driven Process Chains
(EPCs). Building on this analysis, we propose three extensions to EPCs in order to provide for workflow pattern
support. These are the introduction of the so-called empty connector; inclusion of multiple instantiation concepts;
and a cancellation construct. As both the latter are inspired by YAWL, we refer to this new class of EPCs as Yet
Another Event-driven Process Chain (yEPC). Furthermore, we sketch how a transformation to YAWL can be used to
specify the semantics of yEPCs.
]