We are at the beginning of the year 2004 and thus only few weeks away from the enlargement of the European Union to 25 member states. Objective, reliable, and comparative data and information are a prerequisite for European policy to ensure a sound basis for transboundary and harmonised decision making. This is especially true for the field of environmental policy as a cross-cutting issue with numerous links to other policies. The European heads of states stressed at their summit in Göteborg, June 2001: “We are determined to forge a common and coordinated approach to the complex and changing global environment in which we live and the new challenges we face.