This paper examines gender‐specific transformations of nursing practice in institutional mental health‐care in Alberta, Canada, based on archival records on two psychiatric hospitals, Alberta Hospital Ponoka and Alberta Hospital Edmonton, and on oral histories with psychiatric mental health nurses in Alberta. The paper explores class and gender as interrelated influences shaping the work and professional identity of psychiatric mental health nurses from the 1930s until the mid‐1970s. Training schools for nurses in psychiatric hospitals emerged in Alberta in the 1930s under (...) the influence of the mental hygiene movement, evolving quite differently for female nurses compared to untrained aides and male attendants. The latter group resisted their exclusion from the title ‘nurse’ and successfully helped to organize a separate association of psychiatric nurses in the 1950s. Post‐World War II, reconstruction of health‐care and a de‐institutionalization policy further transformed nurses’ practice in the institutions. Using social history methods of analysis, the paper demonstrates how nurses responded to their circumstances in complex ways, actively participating in the reconstruction of their practice and finding new ways of professional organization that fit the local context. After the Second World War more sophisticated therapeutic roles emerged and nurses engaged in new rehabilitative practices and group therapies, reconstructing their professional identities and transgressing gender boundaries. Nurses’ own stories help us to understand the striving toward psychiatric nursing professionalism in the broader context of changing gender identities and work relationships, as well as shifting perspectives on psychiatric care. (shrink)