Marlatt and Gordon’s (1985) cognitive behavioral model of relapse conceptualizes relapse as a “transitional process, a series of events that unfold over time” (Larimer et al., 1999). This is in contrast to alternative models which view relapse as an end-point or ‘treatment failure’. Flexibility is a key advantage of such transitional models: they provide guidance and opportunities for intervening at multiple stages in the relapse process in order to prevent or reduce relapse episodes.