Burgos, España
European judicial cooperation in criminal matters has its origins under Title VI as part of the Third Pillar (JHA) of the Treaty on European Union, signed on 7 February 1992 in Maastricht. Nevertheless, there have been important amendments to this Treaty and to the contents of the Justice and Home Affairs policy through the Treaty of Amsterdam and the Treaty of Nice (the latter in force since last February), such as, for example, the introduction of the European Prosecutors Cooperation Unit (‘Eurojust’). This brief study is concerned with these innovations as well as some legal instruments in the field of criminal judicial cooperation, in particular extradition, mutual recognition of judicial decisions, mutual assistance in criminal matters and the European arrest warrant which are considered as the most relevant.