The purpose of the current study was to determine the extent to which an early prison release incentive impacted inmates' perceptions of substance abuse treatment helpfulness, overall satisfaction and focus on treatment issues. Three groups of inmates participating in their first, third or sixth month of residential drug abuse treatment were surveyed. Overall, findings indicated that the early release incentive served to encourage inmates' engagement in drug treatment and did not appear to distract inmates from perceiving their treatment as helpful or to hinder their pursuit of various treatment topics and skills. Statistically significant differences in what the inmates expected to learn or acquire, overall satisfaction and perceived helpfulness were found between those inmates who were provisionally eligible for the early release incentive versus those who were not. Emphasizing the importance of treatment engagement, an examination of qualitative data also revealed that those who had been in the program longer had higher rates of perceived helpfulness and suggests that at the six-month point in treatment inmates begin to experience and integrate their treatment gains. (Contains 2 tables.)