This book provides a philosophical development of the idea of expressive action. Expressive actions are symbolic actions that mark situations as in some way significant. In expressive action, the symbolism is not arbitrary in relation to what is being marked; rather the symbols speak in some way to the significant features of the situation being marked. A crucial task for the theory of expressive action is to explain what is going on when we engage in such actions. This is the Explanation Question. Many writers have found it difficult, at least on the face of it, to articulate a point to expressive action. The other central question addressed in this book is the Question of Reflective Endorsement: once we know what we are doing when we engage in expressive action, is it something we can continue to regard as worthwhile given the costs involved in it? Christopher Bennett argues that the most adequate answer to the Explanation Question is that in paradigm cases of expressive action we are acting on a distinctive evaluative conception: what he calls the conception of expressive reasons. We take ourselves to have good reason to mark situations through actions in which we attempt to capture, or embody, the significance of the situation. Expressive reasons are a distinctive category of normative reasons. We have good grounds, Bennett argues, to regard them as authoritative standards for the governance of action. On this basis, Bennett claims, we can give a positive answer to the Question of Reflective Endorsement. Bennett also looks at the way in which social conventions, obligations and emotions can be illuminated as forms of engagement with expressive reasons.