Unfortunately each country has its extreme sex offender cases. In 1998 Belgium had outburst of the Dutroux case which had its impact on Belgian laws, the police organisation and other agencies, such as the unit of missing persons. It is worthwhile to mention that most adjustments and reforms of sex laws were introduced before this outburst. Dutroux can be considered as a catalyst. At the end of the nineties the cooperation agreement between the federal state and the communities was established with regard to the guidance and treatment of sex offenders. Nowadays there is a specialized care network for sex offenders, both in psychiatric hospitals and in community teams. Three references centres (one in Flanders, one in Brussels, and one in Walloon) support the specialized care network and are exclusively paid by justice, although one third of our patients are referred on a voluntary basis. Several initiatives were taken to get other sources, for example a collaboration with the Ministry of Welfare to support preventive initiatives, such as Stop It Now! Flanders. In this paper, the organisation of sex offender treatment and quality criteria in Belgium will be discussed. ; unknown