This reserach focuses on how the United Nations, European Union and the Council of Europe are involved in the fight against human trafficking. It follows their main activities and legal documents at different stages of the anti-trafficking effort. A first stage being: defining and criminalizing human trafficking; followed by police cooperation, victim assistance and prevention efforts. This research shows how international cooperation is needed in the fight against human trafficking and how these bodies play an essential role in this respect. It shows that they have managed to secure some achievements, namely providing an internationally recognized definition of human trafficking, and also a framework for police cooperation and victim assistance. However these achievements are clouded by various drawbacks in the way they have been developed and in the way states make use of them. Also these bodies have not been active enough in preventing human trafficking and this research shows that they need to get more involved because national initiatives alone are less effective.