This chapter considers what mental actions are, and how they are best explained. Mental actions are shown to include mental rehearsal of actions, prospective imagining, inner speech, attention, memory search, and (perhaps surprisingly) the spontaneous thoughts that occur while mind-wandering, as well as creative ideas that seemingly occur to one “out of the blue.” The chapter also discusses how controlled sequences of mental action can be explained, and discusses events like judgments and decisions that armchair-philosophers have been apt to claim are mental actions, but really are not.