Choosing not to choose, the latest book by Cass Sunstein (author of Nudge), discusses the benefits one might expect from the generalisation of default rules in our society. The advantages offered by default rules have been corroborated by numerous studies in behavioural economics and have been extensively used to defend a new type of paternalism (Thaler and Sunstein 2008, Sunstein 2014a, b), often referred as referred to as libertarian or behavioural paternalism (Salvat 2014, Rizzo 2016, Lecouteux 2016). While Sunstein’s previous works discuss the benefits of default rules and other paternalistic policies, Choosing not to choose specifically addresses the pros and cons of impersonal as well as personal default rules. Sunstein’s ideas are less ideologically biased and more rigorously argued than in his other books and, more importantly, by introducing a distinction between impersonal and personal rules, he makes a real contribution to the debate on behavioural paternalism.