As components of the therapeutic community (TC) treatment model, the stages define the program’s plan for moving individuals toward the goals of social and psychological change. This chapter describes the process of change in the TC in terms of participation and levels of involvement. It focuses on participation and community as method through the program stages. The chapter outlines some relations between the social and psychological dimensions of individual change and the community expectations for participation. It also describes the process of multidimensional change through treatment in terms of levels of involvement in the community. Participation and involvement link community as method to the individual in the change process. The terms engagement, immersion, and emergence label the individual’s level of involvement in the community. Perceptions related to self and identity are incremental through the levels of involvement.