Policy entrepreneurs are energetic actors who engage in collaborative efforts in and around government to promote policy innovations. Interest in policy entrepreneurs has grown over recent years. Increasingly, they are recognized as a unique class of political actors, who display common attributes, deploy common strategies, and can propel dynamic shifts in societal practices. This Element assesses the current state of knowledge on policy entrepreneurs, their actions, and their impacts. It explains how various global forces are creating new demand for policy entrepreneurship, and suggests directions for future research on policy entrepreneurs and their efforts to drive dynamic change.