Men’s behavior change programs are vital in addressing domestic violence, especially in the Global North. However, studies show high attrition rates, and non-completion is linked to recidivism. There is growing concern about understanding factors that predict program completion. This systematic review examines risk and protective factors influencing engagement in all-male domestic violence perpetrator programs. Conducted in line with PRISMA guidelines, the review analyzed 164 sources from databases like ProQuest and EBSCOhost, ultimately including 80 studies published between 1988 and 2023 from various countries including the U.S., Canada, and the U.K. Through narrative synthesis, the review reveals inconsistencies in defining and measuring program completion, questioning its effectiveness as an outcome indicator. It emphasizes the need for more detailed analyses of program outcomes to capture the complex, relational processes involved in participation and behavior change in these programs. The findings suggest that understanding engagement beyond mere completion is essential for improving program effectiveness and reducing domestic violence recidivism.