In this article, we address the issue of community mental health and the common good via an applied theory of citizenship to support the social inclusion, empowerment, and inclusion of persons diagnosed with psychiatric disorders. We begin by discussing citizenship, and the concept of the common good, in regard to historical conceptions of citizenship, including the historical exclusion of women, people of color, persons with mental illness, and others. We then review the development of our citizenship framework in response to the limitations of even the most innovative community mental health interventions, specifically the practice of mental health outreach to persons who are homeless. We review findings from three citizenship research studies - a community-level intervention, an individual- and group-level intervention, and development of an individual instrument of citizenship - along with brief comments on current citizenship research. We conclude with a discussion of the challenges of realizing both the individual and collective potential of, and challenges to, the citizenship framework in relation to current and future community mental health systems of care.