Process management is becoming more complex especially when business units work together to create new systems constructed from many components. The complexity arises both from the growing number of components and relationships as well as continual changes in product requirements and business arrangements. The complexity impacts on process management as support systems are needed to provide the communications and coordination to support the complex relationships and their continuing change. This paper proposes a systematic way to model such processes by developing the semantics to describe complex processes in meaningful ways. The semantics include perspectives other than those found in process flows to provide a more meaningful way to describe and model complex processes. The paper then outlines ways to convert the models to lightweight platforms that directly support the modeling concepts. The paper shows the application to complex tendering processes, which many of which now require greater flexibility and collaboration.