Data were collected on 286 men who began group treatment in one of eight community programs in the province of Quebec, Canada. The analytical framework for the study was the ecosystemic model, which states that behaviors are the product of the interaction between people and their environment. Men who completed treatment were older, better educated, and had better economic conditions than men who dropped out. They also had a more stable family life, had been in a relationship for a longer period of time, and had more children with their actual spouse. Men who completed treatment showed more commitment, better working capacities, and a higher level of agreement with their therapists, and thus developed a stronger therapeutic alliance. Support provided by people in the environment was significantly related to treatment completion. Social and judicial pressures were not related to completion. The study concludes that if men have been exposed to treatment, even though the exposure may have been very brief, their participation helps them become conscious of the violence of their behavior and of its harmful effects. They become more able to listen to others, more aware of the therapeutic process and available services, and more willing to seek further help. Finally, it is important to consider the cumulative impact of a series of interventions over a period of time rather than to concentrate research on a single event. Tables, references