The acquis communautaire entails the entire body of legislation of the European Communities and Union, that applicant countries must accept before they can join the EU

The acquis is constantly evolving and includes:
- the content, principles and political objectives of the Treaties on which the Union is founded;
- legislation and decisions adopted pursuant to the Treaties, and the case law of the Court of Justice;
- other acts, legally binding or not, adopted within the Union framework, such as interinstitutional agreements, resolutions, statements, recommendations, guidelines;
- joint actions, common positions, declarations, conclusions and other acts within the framework of the common foreign and security policy;
- joint actions, joint positions, conventions signed, resolutions, statements and other acts agreed within the framework of justice and home affairs;
- international agreements concluded by the Communities, the Communities jointly with their Member States, the Union, and those concluded by the Member States among themselves with regard to Union activities.