This chapter describes the system and content of European Union (EU) maritime safety rules. It presents the procedure for internal and external EU action in the field of maritime safety, as well as the actors involved. It explains the roles and responsibilities of EU Member States as flag, port, and coastal States and the tools available to them in the EU legal order, in the areas of prevention, control and surveillance, enforcement, and liability and financial security. It emphasises the importance of implementation and enforcement of international rules, which the EU has made a priority through its maritime safety legislation. It also provides examples of where and why the EU has gone further than international conventions, but also where the EU and its Member States have contributed to the work of the IMO. It deliberates on how the EU legal order ensures effectiveness of its regulatory framework and its role in enforcement – its ‘teeth’. This chapter argues that the EU’s contribution to an international level playing field on safety is pushing for a higher common threshold and ensuring implementation.