Combating and preventing child sexual abuse is one of the most underdeveloped areas of perpetrator work. Working with sexual offenders is one of two types of programmes highlighted in Art. 16 of the Istanbul Convention, stating that countries that ratify the Convention will take “measures to set up or support treatment programmes aimed at prevention perpetrators, in particular sex offenders, from re-offending”. However, it is clear that professionals and organisations need further capacity building in this field. Only properly educated professionals can set up and provide efficient and safe service. This training is an introduction to the topic of working with child sexual offenders, providing an understanding of basic concepts and existing interventions.