Interoperability between public administrations receives nowadays a lot of attention. Also in the European Union interworking is high on the priority list, but the challenges to achieve the European Administrative space are enormous. Many research projects are undertaken, especially in the domain of semantic interoperability. Many of these efforts seem to start from a technical solution rather than from an actual business problem. By taking a narrow view on the problem space, they only promise limited support for the many challenges in the domain of interoperability and innovation of e-Government services. In this paper we present a business driven approach that looks promising in enabling entire classes of interoperability solutions.