The accession of ten new member states to the EU represents a historical milestone for governance and spatial development in Central Eastern Europe. In May 2004, the three Baltic countries Estonia, Latvia and Lithuania, as well as Poland, the Czech Republic, Slovakia, Hungary, Slovenia and the two Mediterranean islands of Malta and Cyprus joined the European Union, thereby profoundly altering the overall institutional map of Europe. As a group, the ten new members are highly heterogeneous, both spatially and socio-economically. Even the former COMECON countries, with their common experience of a rapid transition from centrally-planned to democratic, market-oriented states, have very different regional economic and land use structures, also owing to the diverse political and socio-economic history of the various newly created and reconstituted states. In addition, the transformation processes had different effects on the different societies. In some countries, one can observe a shrinking of the population (Hungary, Czech Republic, Lithuania and Estonia) while others are growing (Poland, Malta and Cyprus).