Evaluating the results of programmes for perpetrators of domestic violence is essential for both policy makers and practitioners, and a growing number of studies have addressed this issue. However, few studies have described the ongoing, day-today outcome measurements routinely undertaken by perpetrator programmes to monitor their results. As part of the IMPACT Evaluation of European Perpetrator Programmes project, in the present study 134 domestic violence perpetrator programmes from 22 European countries answered a survey on the designs, methods and instruments they use in their current day-today outcome monitoring practice and on the obstacles to and need for improvements in this practice. The main results include the findings that 20% of programmes do not measure outcomes at all, that there is a great diversity in methods and instruments used, and a low percentage of programmes make use of data from the victims/survivors and from follow-ups.