Attention toward climate adaptation has been growing among governments over the past decade. In the European Union (EU) alone, nine countries have national plans for adaptation (with more in preparation), there are some 30 sub-national plans, and every Member State has policies to address adaptation. Given the recent attention given toward this subject a question that arises is: can climate change adaptation be considered a policy field? As a unit of analysis, policy fields are widely studied in the social sciences. However, the definition of policy fields such as environmental policy or agricultural policy is taken for granted. Oddly for such a common concept, very little attention is paid to what policy fields are in and of themselves or how they can be identified. Given these shortcomings, this article first attempts to fill this gap by theoretically defining what a policy field is by identifying and assigning their characteristics and dynamics. Based upon a literature review, it shows that policy fields are three-dimensional entities comprised of substantive authority, institutional order, and substantive expertise. The second task of this article is to apply this definition to adaptation policy activity in England and determine whether adaptation can be considered a policy field there. © 2012 Springer-Verlag.