The European Geoportal has been identified as one of the building blocks of a European Spatial Data Infrastructure (ESDI). The vision of the EU Geoportal is to allow users to discover, understand, view, access, and query geographic information of their choice from the local level to the global level, for a variety of uses, such as environmental policy development and impact assessment, land use planning, natural disasters preparedness, monitoring, and response. The EU Geoportal will facilitate links and coherence with many institutional servers and portals and will provide on-line access to collections of spatial data and services supplied by multiple public and private organisations.

This paper presents some of the work associated with the establishment of an ESDI, and the requirements for the EU Geoportal. The prototype version of the EU Geoportal demonstrates the feasibility to link distributed geographic information services but at the same time reveals a number of challenges that need to be considered in the path towards interoperability. The current obstacles related to technological interoperability issues are discussed in detail and proposals are made for the next steps to be taken to speed up the implementation of the ESDI.