This symposium of Critical Policy Studies shares the concern for systematic empirical evaluations of the extent to which arguing and deliberation are relevant for explaining outcomes in the real world of public policy. The articles contribute to a growing body of literature on the conditions under which deliberative practices matter in politics. They provide rich empirical materials, and each article is based on solid and methodologically conscious research. My comment proceeds in three steps. First, I discuss three logics of action – consequentialism, appropriateness and deliberation. Second, I comment on the scope conditions under which arguing and deliberation are likely to affect the outcomes in public policy, with an eye on the contributions in this symposium. Third, I discuss the role of Habermasian ‘power in discourse’ and its relationship to a Foucaultian ‘power of discourse’. I conclude with remarks on the normative implications of the focus on deliberation.