Social work has had a long concern for people experiencing different forms of social injustice. This chapter sets out the history of social work debates about knowledge concerned with the shape of the discipline and profession of social work and then traces a history of practice responses that give social work its distinctive form. Despite changes in contemporary conditions, since its beginnings, social work continues to adapt its focus to challenge forms of injustice, disadvantage and social conditions that impact the well-being of individuals, families, groups, communities and societies.