This chapter sets out the general contours of a Marxist approach to the study of public law. It begins by setting out some of the core elements of Marxist analysis, namely historical materialism and class antagonism, and noting the general relevance of these foundational principles for Marxist approaches to law in general. The chapter then looks at the Brexit conjuncture, and the central public law dilemmas associated with it, revolving in particular around the role of the courts, to illustrate the application of a Marxist analysis to the study of public law. Finally, the chapter considers what the implications are for a Marxist approach to public law when the issue arises of ‘socialist constitutionalism’.