This review takes stock of the new literature on ideas and policy making. It identifies different types of ideas that have received attention in policy research, discusses how they affect policy making, and addresses some of the more important problems social scientists need to solve in studying them. In particular, this review shows that scholars need to better specify the causal mechanisms by which ideas of various sorts affect policy making, and it suggests some ways in which this might be better done. The new literature is more open to the possibility of interplay between ideas and interests.
