Philosophers of action have rarely systematically thought about acts of communication as special sorts of actions, nor have speech act theorists looked on the bearings of the general theory to action on linguistic acts. This dissertation represents an attempt to work seriously within precisely that intersection of action theory and speech act theory. Some problematic issues in both areas can, from this combined perspective, be reformulated more clearly than they have been previously articulated. ;The first part of the thesis examines (...) linguistic communication as a subspecies of action, formulating a unifying theoretical description of speech and action. The distinction between constitutive rules and regulative rules turns out to parallel a distinction between basic actions and nonbasic actions; I explore the usefulness of the concept of level-generation and basic actions in the context of the theory of linguistic communication, arguing for a conception of basic speech acts. ;The second part of the thesis provides a theory of demonstrative utterances. A demonstrative utterance is simply an utterance accompanied by a demonstrative gesture. The account offered supplies a speech act-like analysis of demonstrative as well as an action-theoretical analysis of the gestures which accompany demonstrative utterances. This theory addresses and answers many of the questions raised by Kaplan and passes beyond them to offer insight into the communicative aspects of demonstrative uses of expressions. I extend this analysis to cover the wider class of all utterances accompanied by relevant gestures as a prologue to the more comprehensive study of nonverbal communicative behavior. ;In the third part I show how the concepts of the unified theory developed in parts I and II, form the building blocks of a general theory of nonverbal communicative behavior. I examine the structure of statements about meaningful action and nonverbal behavior as well as the properties of the behavior itself. I argue that only accounts which include elements of both action theory and the theory of communication can successfully explain the nature of nonverbal communicative behavior as the sort of action that is properly said to be meaningful. (shrink)