 The concept of a nudge was introduced by Cass Sunstein and Richard Thaler to refer to the deliberate introduction of subtle, non-coercive influences into people’s decision-making to get them to make more optimal choices (Thaler &amp; Sunstein 2009; Sunstein 2014). Some nudges merely provide better and more comprehensible information; these nudges might seem best characterized as influences that improve the quality of rational deliberation. However, even with “purely” informational nudges, one might worry that the selection of which information is presented could be manipulative; perhaps providing nutrition information on food packaging nudges people to make food choices based on health considerations rather than taste, for instance. More pressing concerns arise with nudges that operate by psychological mechanisms whose relationship to rational deliberation is questionable at best. Many of these nudges exploit heuristics, reasoning and decision-making biases, and other psychological processes that operate outside of conscious awareness. For example, some evidence suggests that patients are more likely to choose an operation if they are told that it has a 90% survival rate rather than a 10% fatality rate. Would it be manipulative for a surgeon to exploit this framing effect to nudge the patient into making the decision that the surgeon thinks best? Is it manipulative for a cafeteria manager to place healthier food items at eye level to nudge customers into choosing them? The question of whether and when nudges manipulate has sparked a lively debate.