Ernesto Laclau has blazed a unique trail in political theory and philosophy since the early 1970s. In so doing, he has articulated a range of philosophical and theoretical currents into a coherent alternative to mainstream models and practices of conducting social and political science. His revitalization of Marxist theories of politics and ideology in the 1970s gave way to the elaboration of a distinctively post-Marxist theory of discursive practice in the 1980s and 1990s, in which he draws together a diverse range of theoretical sources into a coherent approach to social and political analysis. Stretching back to his critiques of Louis Althusser, Nicos Poulantzas, Ralph Miliband and Immanuel Wallerstein, Laclau has also developed this approach in a series of critical engagements with the leading social and political theorists of the time. These include debates and engagements with Giorgio Agamben, Alain Badiou, Judith Butler, Joan Copjec, William Connolly, Simon Critchley, Jacques Derrida, Jacques Rancière, Richard Rorty, Linda Zerilli, and Slavoj Žižek. His most recent book ߝ On Populist Reason ߝ provides an innovative approach to the construction of collective political identities, and further fleshes out his original theory of hegemony.
The book highlights four areas of scholarship:

1. Post-Marxist Political Theory. Laclau has developed an original conception of post-Marxist political theory that is grounded on a materialist theory of discourse. The latter is constructed from a range of theoretical and philosophical sources, including poststructuralism, psychoanalysis, linguistic theory and post-analytical philosophy. The centerpiece of this approach is the category of hegemony, which develops Antonio Gramsci’s seminal contribution to Marxist theory, and is in turn connected to a web of related concepts, including articulation, dislocation, the logics of equivalence and difference, political identification, myth and social imaginary. These ideas have informed a number of empirical and theoretical studies associated with the Essex School of Discourse Theory.
2. The Question of Populism. A central concern of Laclau’s writings has been the problem of populism, both in Latin America where Laclau began his interrogation of the phenomenon (especially the experience of Peronism), and then in his engagement with the "new social movements" and socialist strategy more generally. The concept of populism becomes a general way of exploring the "primacy of politics" in society.
3. Critical Engagements. Laclau is first and foremost an engaged intellectual who has consistently sought to "theorize" contemporary events and reality, and to debate with the leading intellectual figures of the day, with respect to questions of political principle and strategy. His recent debates with Judith Butler and Slavoj Žižek in the book Contingency, Hegemony, Universality (London: Verso) exemplify this critical ethos. He continues to elaborate his approach by challenging and articulating related approaches, and by situating his work in connection to the Democratic Left.