This discussion asserts that legal theory is being transformed by postmodern and critical social theory. The author argues that legal theorists should familiarise themselves with postmodern legal and social theory, as postmodernism could potentially fundamentally alter the legal meaning of agency, rationality, and intention.;The aim of the text is three-fold. Firstly, it sets out the work of four particular scholars of critical social theory, all of them Continental Europeans - Jurgen Habermas, Michel Foucault, Jacques Derrida and Jacques Lacan. Secondly, it seeks to demonstrate that although the work of Foucault, Derrida and Lacan is often juxtaposed to that of the arch (neo-)liberal social theorist Habermas, all four scholars of this small corpus share similar philosophical roots. To this end, it particularly refers to the original formation of critical theory by the early Frankfurt School of Critical Theory (the Frankfurt School); their contribution to critical social theory specifically, and philosophy more generally. Thirdly, it analyzes, with respect to Derrida and Habermas, and to a lesser extent Foucault and Lacan, the two issues that opponents of the postmodern approach argues to be the Achilles' heel of postmodernism: does postmodernism introduce a pernicious relativism to judgement, making ethics and values a performative impossibility? And does postmodernism have any implications for the practice of legal reasoning, legal rationality, and our understanding of both legal agency and legal ide