As a member of the European Union, the Spanish economy has changed dramatically. Once economically isolated within the Iberian Peninsula, Spain has evolved from a backward economy to a dynamic European leader. However, the current economic crisis has posed new challenges to the Spanish economy. We will consider how EU membership has influenced economic development, investment, labor relations, and entrepreneurship in the country. Political, social, and business aspects will also be studied. Special reference will be made to the impact of economic and monetary union (EMU) on the economy and to the effects of the 2008 crisis.