Workflow and Web Services have the main role in the development and in the realisation of B2B architectures. In this context, the principal target is to compose many services supplied by different providers creating new value added services. The Web Services technology provides the base for realising complex business processes through the composition of Web Services: literature proposes, at the moment, two principal approaches to the coordination of network services: orchestration and choreography. In this paper we propose a framework for characterising the components of a business process which can be detected inside existing workflows. We define a collection of structural and non-structural criteria, which allow the constitutive parts (components) of a workflow to be characterised. Targets can be different: these criteria can be used to search for reusable components into existing workflows, but also to verify if a given business process is able to support specific missions.