BPMN (Business Process Model and Notation)
BPMN (Business Process Model and Notation) is the graphical notation standard for modeling business processes standardized by the Object Management Group (OMG). BPMN 2.0 models are equally readable for business and IT and can be executed directly by workflow engines — the diagram is thus both documentation and executable process.
The core elements of the notation
BPMN describes processes with a fixed, standardized vocabulary of symbols. A manageable set of core elements is enough to get started:
| Element | Representation | Meaning |
|---|---|---|
| Events | circles | Something happens: process start, process end, incoming message, timer |
| Activities | rounded rectangles | Work steps — performed by people (user task) or systems (service task) |
| Gateways | diamonds | Branches and merges of the flow: exclusive, parallel, event-based |
| Sequence flows | arrows | Order of the steps |
| Pools & lanes | rectangular containers | Responsibilities: organizations, departments, roles |
| Data objects | document symbols | Inputs and outputs of a work step |
In total, BPMN 2.0 comprises well over 100 symbols — in practice, the majority of models get by with this small subset.
From diagram to executable process
The decisive difference to older process notations: in addition to the graphical representation, BPMN 2.0 defines an XML exchange format with precise execution semantics. A workflow engine — such as Camunda 7 or its open-source successor Operaton — executes the model directly: it controls the order of steps, distributes tasks to people and systems, monitors deadlines and documents every run.
The process model is thus not a picture next to the code, but the process itself. What is orchestrated are typically the workflows in which the actual value creation happens: applications, approvals, dispatching, risk assessments, claims.
BPMN vs. simple flowchart
At first glance, a BPMN diagram looks like a flowchart — the differences lie in the level of rigor:
- Standardized semantics: Every BPMN symbol has a clearly defined meaning. A flowchart is interpreted differently by every reader.
- Exchange format: BPMN models can be exchanged between tools as XML instead of being tied to a single drawing program.
- Executability: A sufficiently precise BPMN model runs directly on a workflow engine.
- Responsibilities and exceptions: Pools, lanes and timer, error and escalation events make visible what flowcharts usually leave out — who is responsible and what happens in case of deviations.
BPMN in practice: the model has to live
The value of BPMN does not come from the diagram, but from its use. In our experience, models that are maintained only as documentation quickly become outdated; executed models inevitably stay current because they are the process. Just as important is the order of work: first understand and clean up the real workflow with the people involved, then model it. A bad process is only written down more precisely by BPMN — not made better.