Since the 1990s trafficking in human beings has increasingly become a priority in the international and European policy agenda. The international community took action against it with the United Nations Protocol against Trafficking (2000), the Council of Europe Convention on Action Against Trafficking in Human Beings (2005) and the Directive 2011/36/EU of the European Parliament and of the Council on Preventing and Combating Trafficking in Human Beings and Protecting its Victims. In the same period the number of studies and research works on it has increased. Nevertheless, some of the most important research questions remain almost unanswered. In particular, there is a paucity of data about the effectiveness of the policies against human trafficking. This paper provides some knowledge in this field. In particular it presents some considerations on the effectiveness of the Italian policies on the protection of and assistance to victims in the period 2000-2008. The data analysis suggests that the effectiveness varied across years and that the entry of Romania in the European Union, apparently, had an impact on the phenomenon and on the policies effectiveness. The lesson to be learned is that under the umbrella of human trafficking very different situations, changing across time and countries, coexist. In order to be effective a national policy should be capable of a) planning actions which take into account the national characteristics of human trafficking; b) monitoring whether and how the phenomenon has changed and change the policies accordingly.