Do governments have the right to influence citizens’ behaviour related to smoking tobacco, eating too much, not saving enough, drinking alcohol or taking marijuana? Or does this create a nanny state, leading to infantilisation, demotivation and breaches in individual autonomy? In this Vox Talk, Julian Le Grand – co-author with Bill New of ‘Government Paternalism’ – discusses the lessons from behavioural economics about human mistakes and the potential for the state to guide citizen decision-making in positive ways.