In order to create, share and improve knowledge on business processes, humans need a common, readable and preferably visual notation. So far, a lot of effort has been put into visualisation of process definitions (e.g. the recently published Business Process Modelling Notation - BPMN). In this paper we propose to put equal stress on visualisation of process execution, thus allowing process performers to understand the process history, its current state and possible future execution. We define a process instance notation as an extension of BPMN. The underlying premise for this approach is the reuse of well-defined and commonly accepted concepts from the process definition level on the process instance level. The prototype implementation is being integrated within the ICONS knowledge management platform.