Behavioral science units across the world advise policy makers on the use of nudge techniques with the goal to improve health, wealth, and happiness. Nudges use psychology to steer people toward or away from making particular choices by designing choice architectures that frame or highlight options in particular ways. What has been missing from debates on nudging is a systematic consideration of the environments in which they are embedded. We argue that a detailed examination of the wider environment in which the policy issue is situated is essential for designing, implementing, and evaluating policy-making tools, nudge-like or otherwise. Successful policy making requires a good fit between intervention and the environment, otherwise we risk miscasting policy issues and designing futile interventions. Using real-world cases, we characterize the role of the environment in different policy problems and present a basic taxonomy for policy makers to identify critical factors in the environment beyond the confines of the choice architecture.