Articulating and representing work knowledge in models in a contextual and traceable form is an essential part of Business Process Management (BPM) activities in ecosystems of the platform economy. These ecosystems have significantly changed the way what motivates people to participate, how work is organized and how the networked stakeholders communicate. Such issues have in turn led to methodological challenges in acquiring process-relevant knowledge and mapping it to executable representations. This paper targets the perception of tasks of individual role carriers in the platform economy, and offers a corresponding elicitation and documentation scheme that finally supports the specification of business process models. Contextual process knowledge acquisition and representation is suggested applying Ricœur’s concept of Narrative Identity. Self-knowledge is captured by individual stories on task-relevant information and interaction. The stories are analyzed by means of Rhetorical Structure Theory to identify information on business processes. The resulting representation facilitates business process modeling and validation. A first case study utilizing subject-orientation confirms the approach’s potential and helps identifying topics for further research.