This chapter draws on the conceptual ideas of Michel Foucault to provide a critical account of power as it is brought to bear on, used by and shapes social work. The chapter begins by highlighting the debate about care versus control within social work, as well as raising a number of fundamental questions about the allegedly progressive nature of developments within social work over the last century. Foucault’s concepts of ‘discourse’, ‘governmentality’ and ‘surveillance’ are dealt with both on their own terms and in relation to one another, as they combine to create a critique of the nature and operation of state and professional power in modern society. The applied section of the chapter uses these concepts to critically explore the social work relationship, the ‘e-turn’ within social work and the marginalization within social work education of social theoretical forms of knowledge.