Enterprise

EPC

August-Wilhelm Scheer’s notation based on alternating events and functions linked by logical connectors. The de facto standard for SAP projects and the ARIS platform.

EPC — event-driven order fulfilment
EPC — event-driven order fulfilment
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How it came about

The Event-driven Process Chain (EPC) was developed in the early 1990s by Professor August-Wilhelm Scheer together with SAP AG, within the ARIS (Architecture of Integrated Information Systems) framework. The notation quickly became the de facto standard for SAP R/3 implementation projects, and by 2000 the ARIS platform counted more than 8,000 enterprise customers worldwide.

Basic principles

EPC is built on the alternation of two kinds of nodes:

  • Events — passive elements denoting a state or a change that has occurred. Drawn as a hexagon.
  • Functions — active elements describing an action or procedure. Drawn as a rounded rectangle.

Between events and functions sit logical connectors: AND (&), OR (∨), XOR (×). They control branching and synchronization of the flow.

Correctness rules

The EPC notation imposes strict rules:

  • An event cannot be followed by an XOR/OR connector (an event is passive; it makes no decisions)
  • A function cannot be immediately followed by another function without an event in between
  • Every branch opened by a connector must be closed by a connector of the same type

These rules ensure the model is semantically correct and unambiguous.

The extended notation — eEPC

Extended EPC (eEPC) adds to the basic notation:

  • Organizational units — who performs the function
  • Information objects — what is used and produced
  • IT systems — in which systems it runs
  • Goals and risks — for what goals and with what risks

eEPC gives a full, multi-perspective description of a process and is the most common in enterprise practice.

Strengths

  • High readability for a business audience
  • The “event-function” logic is intuitive
  • Rich eEPC extensions cover the organizational context
  • Deep integration with ARIS — a powerful model repository

Limitations

  • Low executability — models are rarely used for automation directly
  • Lock-in to the ARIS / SAP ecosystem
  • Diagrams become bulky with many events
  • Less international popularity outside German-speaking countries