Interoperability between different organizations is a complex task, where a key element is to be able to define without ambiguity the concepts that are involved in each domain and their relations. A key aspect for enabling e-government is the technological support for complex interaction scenarios, defining collaborative Business Processes (BPs) that are the basis for these interactions. E-government collaborative BPs involve several and heterogeneous participants: organizations, partners, and users, with different capabilities, needs, and available technical support. The goal of this paper is to present ongoing research on e-government cross-organizational collaborative BPs support in a service-based interoperability platform. This proposal is focused on the formalization and exploitation of e-government knowledge and information (i.e., metamodels and ontologies) to improve the definition, automated generation, control, monitoring and improvement of e-government collaborative BPs
