The EU's deregulation programme for the airline industry has been under way since 1987 and the final stage, implemented on April 1 1997, gives all EU carriers free access to domestic routes in all EU countries. However, it still allows governments to give preferential treatment to national airlines. In its extreme form, this involves large State subsidies, particularly in the Mediterranean countries. There also exist monopolies on ground services, inadequate pan-European air-transport infrastructure and many airports and airlines in Europe are still State-owned. These factors restrict free trade in practice. Several European airlines have requested the EU's Court of First Instance to reverse the EU Commission's decision to allow state subsidies.