Business Process Modelling Notation (BPMN) is a standardised diagram notation for modelling interactive workflow processes graphically at the design stage. The primary objective of this thesis is to provide a framework for precise specifications and formal verifications of workflow processes modelled as BPMN diagrams. We provide two behavioural semantics for BPMN in the process algebra Communicating Sequential Processes (CSP). We apply existing CSP refinement orderings to both the refinement of business process diagrams and the verification of behavioural compatibility of business process collaborations. The first semantic model is an untimed model, focusing on the control flow and communication of business processes. The second semantic model extends the first one to capture the timing aspect of behaviour.

We also consider the applications of the semantic models. The secondary objective of this thesis is to apply BPMN and the semantic models to reason about long running empirical studies (e.g. laboratory experiments, clinical trials). We introduce a declarative workflow model Empiricol for recording trials and experiments precisely, and define bidirectional transformation functions between BPMN and Empiricol. Using the transformation functions, we make graphical specification, simulation, automation and verification of trials and experiments possible. We provide two case studies on the applications of BPMN’s formalisations.