The development of social science research methods by women reformers in the late nineteenth and early twentieth centuries is a largely buried history. This article examines the work of Clementina Black and Margaret Harkness, two British reformers who conducted many social investigations using a wide range of research methods. They also crossed genres in writing fiction, which was an accepted method at the time for putting forward new ideas about social conditions. Black and Harness were part of a vibrant network of women activists, thinkers and writers in late nineteenth century London, who together contributed much to the growing discipline of social science and to imaginative forms of writing about social issues.