We present a case study of the use of Dynamic Con- dition Response (DCR) Graphs, a recently introduced declarative business process model, in the design of a cross-organizational case management system being developed by Exformatics A/S, a danish provider of knowledge and workflow management systems. We show how DCR Graphs allow to capture directly both the behavioral constraints identified during meetings with the customer and the operational execution as markings of the graph. In comparison, imperative models such as BPMN, Petri Net, UML Sequence or Activity diagrams are only good at describing the operational way to fulfill the constraints, leaving the constraints implicit. In particular, we point out that the BPMN ad-hoc sub process activity, intended to support more loosely structured goal driven ad-hoc processes, is inconsistently described in the final version of the BPMN 2.0 standard. The case study motivated an extension of the DCR Graphs model to nested graphs and the development of graphical design and simulation tools to increase the understanding of the models. The study also revealed a number of challenges for future research in techniques for model-driven design of cross-organizational process-aware information systems combining declarative and imperative models.
International Enterprise Distributed Object Computing Conference. Proceedings, 2011, p. 161-170