Research on the transtheoretical model has provided substantial support for both stages of change and processes of change (coping strategies influencing successful behavior change). This study examined whether timing of process use (using particular change processes during one stage and not during others) influences quit success. Hypothesized patterns of optimal process use were those marked by more use of experiential processes and less use of behavioral processes during contemplation and preparation and by the reverse pattern during action. Participants (N = 388) began in contemplation or preparation and took action during a 4-6 week period. Multivariate analyses of covariance examined the relationship between patterns of process use and success in staying quit both at 1-month follow-up and 5-6 months later. For the most part, results supported the hypothesis that successful stage transitions involve doing the right thing at the right time: engaging in experiential process activities during contemplation and preparation stages and shifting to behavioral process activities during action.