European Union (EU) competition law is relevant to all businesses of all sizes in all member states. It applies to agreements between competing businesses, mergers, acquisitions and the actions of businesses with a large share of their market.
Competition law also limits the amount of help - known as 'state aid' - which governments can give to businesses in their country which may give them an advantage over competitors in other member states.
This guide explains the main areas of European Union competition law - including how these rules affect cartels, mergers and state aid, and promote liberalisation. It also explains international co-operation on competition law and the role of the European Competition Network.