Young people who attend intensive alcohol and other drug (AoD) treatment commonly do so more than once. This paper aims to understand precipitators, enablers and barriers to young people's re-engagement in programs. Data come from a longitudinal qualitative study involving three waves of interviews with Australian young people recruited while attending intensive AoD programs (n = 38 at wave 1). We found that young people's ambitions for what they might achieve with a new stay and capacity to benefit from programs, evolved. Skills learnt in earlier stays or changed life circumstances often helped them achieve better outcomes subsequently. Ongoing contact with an AoD worker was the most important enabler to service re-engagement. Across the span of a year, we saw most young people in our study sample develop a stronger sense of wellbeing and control over substance use. While researchers tend to focus on evaluating outcomes associated with single stays at specific programs, young people think about their trajectories towards managing substance use and their lives as occurring more holistically, supported by engagements with a range of services. We argue that the notion of incremental treatment is useful in depicting the synergistic effects of service engagement over time.