Over the past years research in pervasive computing has demonstrated the potential of context-aware and proactive technologies for improving human work performance and to ensure that people act compliant according to predefined regulations. Human work can be structured into tasks, whereas a task is representing an atomic human work entity. A person-centric flow is an IT-representation of the flow of activities an individual person is performing. For example the daily care schedule of a nurse can be understood as the person-centric flow of the nurse. To be able to effectively guide a person in a complex and highly dynamic work environment and to react on possible deviations from the flow the supporting system is required to be aware of the state of the person-centric-flow. Beside guidance the flow information can be utilized to check compliance of a person’s flow with prescribed sequences of operation. In this paper we propose a constraint-based workflow model for person-centric flows and an event-model which can be used to inform applications about the state of these flows.