Philosophers since Aristotle have always been concerned with human action, but to a very significant degree this concern has been subservient to problems in other philosophical disciplines such as ethics, philosophy of law, metaphysics, logic, philosophy of language and even artificial intelligence. This exposé on the philosophy of action more or less reflects this tradition, without denying that in the latter half of the 20th century influential books and articles in the philosophy of action have shaped discussions in ethics, philosophy of mind, speech act theory and pragmatics. To act is to bring about something. An agent is that which brings the action about. This invites us to look at the mental antecedents of what happens in order to understand the bodily movements. The classic move is to say that an agent’s reasons play a central role in identifying and explaining action. This idea goes back to Aristotle. A related theme in Aristotle’s view of action is that the presence of a mental antecedent is a necessary condition for something’s being an action. Bodily movements are preceded by wishes, desires, volitions or intentions. In one form or another, this view has been defended by Locke, Hume, Mill, Prichard, Wittgenstein and Ryle. A central problem, however, remained: is the mental antecedent we point to when we explain an action also the cause of that action? Aristotle accepted that the reasons one has for acting are also the causes of the action, and Hume, Locke and Mill sided with him on this issue. Under the strong influence of the writings of Ludwig Wittgenstein, however, twentieth-century philosophers are deeply divided over this issue. A major obstacle to the acceptance of the causal view was the famous logical connection argument defended by Wittgenstein (1953). The anti-causalist view does not necessarily deny that actions are caused. A proponent of that view may or may not accept the view that there are actually two different kinds of causal relations: event causation and agent causation. This view, however, was eventually rejected on the basis of strong ontological considerations. Introducing two radically different kinds of causality makes intentional action into something entirely magical. This, however, is not sufficient as an argument against the Wittgenstein-inspired ‘logical-connection argument’. The argument can be rejected on the following grounds: rational agents act on the outcome of a practical syllogism. Aristotle defined the outcome of such a syllogism as the action itself, but this view came under pressure because actions (non-semantical entities) can never have logical connections with sentences (semantic entities) (see Davidson 1980). The distinction between what persons do and what happens to them is drawn in terms of how we explain what they do. The ‘multiple-description’ thesis underlying this view (actions are particular events verifying different descriptions) is a central issue in contemporary philosophy of action (see Anscombe 1957). It reveals that the old distinction between what an agent intentionally does and what happens to him is an intensional distinction. This solution (based on Davidson 1980 and going back to Anscombe 1957) is now generally accepted as the best counter-argument against agent causality. It can shed an interesting light on the relation of freedom and determinism. The debate over freedom vs. determinism in action is connected to a problem in the philosophy of mind: that of reductionism. The intentional stance (see Dennett 1987) or the point of view of the interpreter (Davidson 1984) is necessary to see someone perform actions (and not merely to see his body moving in this or that way). This refers to still another point, viz. the relation between action and responsibility. Many technical insights in philosophy of action were developed and/or used by J. L. Austin, whose seminal work How to do things with words (Austin 1962) had a major influence on the emerging field of pragmatics. Austin, who was well aware of the importance of insights in the philosophy of action for speech act theory, used in fact a great many insights in his work: the distinction between the locutionary, illocutionary and perlocutionary actions is a distinction on the level of descriptions of actions; perlocutionary actions are distinguished from illocutionary actions because they are described in terms of the (intended) effects the speaker wants to bring about in the hearer. J. R. Searle’s Speech acts (Searle 1969) made speech act theory a semi-autonomous discipline whose main sources were no longer the philosophy of action but the philosophy of language and linguistics.