In what follows, I will contend that the commonsense view of ourselves as fundamental causal agents - for which some have used the term ''unmoved movers" but which I think might more accurately be expressed as ''not wholly moved movers'' - is theoretically understandable, internally consistent, and consistent with what we have thus far come to know about the nature and workings of the natural world. In the section that follows, I try to show how the concept of `agent' causation can be understood as a distinct species (from `event' causation) of the primitive idea, which I'll term ''causal production'', underlying realist or non-Humean conceptions of event causation. In section III, I respond to a number of contemporary objections to the theory of agent causation. Sections IV-V are devoted to showing that the theory is compatible with ordinary reasons explanations of action, which then places me in a position to respond, in the final section, to the contention that we could never know, in principle, whether the agency theory actually describes a significant portion of human activity.