The generative literature on idiomaticity often discusses constraints on the structural contexts in which special idiomatic meanings can arise. This chapter focuses on one such proposed constraint, the ‘No Agent Idioms’ hypothesis of Marantz. It argues that this hypothesis is tenable, in spite of several proposed counterexamples to the generalization. Many apparent counterexamples are not true counterexamples as their argument structure has significantly different properties than that of agentive structures. Some have external objects with the properties of Causers rather than Agents, while others appear to be idiomatic DPs rather than subject-verb idioms. In addition, the chapter argues that a context-dependent, structural approach to idiomatic meaning such as the one taken here is more consistent than a ‘phrasal lexicon’ approach with a central tenet of linguistic theory, namely the compositionality hypothesis. This suggests that the context-dependent meaning view of idioms has some advantages over the ‘phrasal lexicon’ approach.