This thesis describes the life and work of Individualpsychologist Sofie Lazarsfeld (1881-1976). It containes an extended biography, additional interviews with her grandchildren and correspondence between Friedrich Adler and Sofie Lazarsfeld, Elin Wägner and Sofie Lazarsfeld. Secondly the dissertation focuses on Sofie Lazarsfelds writings about individual psychology and pedagogy and female self-development. The change in education of children and women was for Sofie Lazarsfeld the main subject in the Individualpsychology. At the same time she was involved with consulting in Individualpsychology she also fought for political changes.