The author outlines the social and political context in which the TPC was located, specifically its role in the production of knowledge that was used by the leadership organ of the mental hygiene movement, the Canadian National Committee for Mental Hygiene, for its own ideological and propagandistic purposes. The author examines the technology of the clinical investigation itself to consider its deployment in relation to young working-class women who were its "patients." This involves determining what social, moral, and economic criteria were used in assessment and diagnosis. Finally, the paper surveys the institutional apparatus that was used in "treatment." This apparatus involved a developing network of institutions used or at least recommended by the TPC practitioners to perform a continuum of functions that ranged from incarceration -- temporary, indefinite, or permanent -- to community surveillance and supervision, with recommendations for vocational training and deportation for immigrants. The author notes that as an agency that existed on the periphery of the "official" state, the TPC succeeded in adding another layer of professionalized intervention into the personal lives and identities of young working-class and immigrant women whom clinic practitioners sought to regulate, even in the absence of enabling legislation. 68 notes