ERSA is the supranational grouping of national regional science associations across Europe. Members are academics, policy professionals and researchers interested in spatial economics and planning, regional and local development and related issues. They are drawn largely from the disciplines of economics, geography and planning. There are presently 17 active associations (commonly named 'sections'), some, such as the German or French speaking sections, organized on linguistic groupings and covering more than one country. Constituent associations range in size from more than 700 members to 27. The largest sections have their own national professional organizers. In total ERSA has some 3500 members in its constituent associations.