Abstract : Business Process Management (BPM) principles are commonly used to improve processes within an organization. But they can equally be applied to supporting the design of an Information System (IS). In a collaborative situation involving several partners, this type of BPM approach may be useful to support the design of a Mediation Information System (MIS), which would ensure interoperability between the partners’ Information Systems (which are assumed to be service-oriented). To achieve this objective, the first main task is to build a collaborative- business-process cartography. The aim of this article is to present a method for bringing together collaborative information and elaborating collaborative business processes from the information gathered (with the help of a collaborative situation framework, an organizational model, an informational model, a functional model, and a metamodel, and by using model transformation rules).