This book explores how notions of deviancy and social control are dramatized in the novels of the late nineteenth-century Spanish realist author Benito Pérez Galdós. Galdós’s treatment of prostitutes, alcoholics, beggars and vagrants is studied within the context of the socio-cultural and medical debates circulating during the period. Drawing on Foucault’s very specific conceptualisation of the idea of control through discourses, the book analyses how Galdós’s novels interacted with contemporary debates on poverty and deviancy – notably, discourses on hygiene, domesticity and philanthropy. It is proposed that Galdós’s view of marginal social groups was much more open-minded, shrewd and liberal than the often inflexible pronouncements made by contemporary professional voices.