FORUM Discourse, explanation and critique David Howarth a , Jason Glynos a and Steven Griggs b * a Department of Government, University of Essex, Colchester, UK; b Department of Politics and Public Policy, De Montfort University, Leicester, UK It is often alleged that post-structuralist discourse theory suffers from a methodological and a normative deficit, making it unable to either explain or criticize and evaluate the policy practices and regimes it investigates. We challenge such claims, arguing instead that post-structuralist discourse theory is both explanatory and critical. We begin by providing a quick sketch of how the ontological assumptions of post-structuralist discourse theory translate into a novel approach to policy studies, one which fore- grounds the critical evaluation of policies and practices in order to explore underlying issues of power and ideology. We then discuss what we term to be the critical dimension of critical explanation. Here we foreground in our discussion how the assumption of radical contingency, the articulation of social, political and fantasmatic logics, and a novel perspective on ethical critique and normative evaluation can offer policy researchers the opportunity to go beyond the strategy of simply inverting existing hierarchies and binary oppositions to project more positive ontopolitical presumptions. Keywords: post-structuralism; logics; discourse; critique It is often alleged that post-structuralist discourse theory (PDT) suffers from a methodo- logical and a normative deficit. Some argue that the approach does furnish a grammar of notions that can help us to describe and characterize phenomena, but it cannot explain them. Others claim that while it may help us to describe, and even explain, it cannot criticize and evaluate the policy practices and regimes it investigates (for further discus- sion, see Glynos and Howarth 2007). We respond to these two challenges by arguing that PDT is both explanatory and critical. The general form of the claim is not, of course, unique. First generation theorists of the Frankfurt School such as Max Horkheimer (1972) argued for a close connection between explanation and critique. Critical realists like Roy Bhaskar (1986) and Bob Jessop (1990) argue for a practice of ‘explanatory critique’ in the social sciences. However, in speaking as post-structuralist discourse theorists, our grounds for justifying the linkages between explanation, critique and justification are different, as is the overall approach to such questions. Discourse theory and critical policy studies The basic assumptions of PDT and its radical materialist conception of discourse have been thoroughly set out and discussed elsewhere (see Howarth 2000, 2013). Here we begin by providing a quick sketch of how its ontological assumptions translate into a novel approach to policy studies, which foregrounds the critical evaluation of policies and practices in order to explore underlying issues of power and ideology (for *Corresponding author. E-mail: sgriggs@dmu.ac.uk Critical Policy Studies, 2016 Vol. 10, No. 1, 99–104, http://dx.doi.org/10.1080/19460171.2015.1131618 © 2016 Institute of Local Government Studies, University of Birmingham