This research examines the role of leaders for employee recovery. We hypothesize that leader support for recovery (empathy for recovery, respect for boundaries, and role modelling) relates positively to employees' psychological detachment from work during non-work time that, in turn, predicts well-being outcomes. We argue that leader support for recovery can only be effective when the leader-member exchange (LMX) relationship quality is sufficiently high. In a series of scale-development and scale-validation studies, we demonstrated the construct and content validity of a new measure of leader support for recovery. We tested our hypotheses with diary data collected from 152 employees. Respect for boundaries was positively related to employees' psychological detachment from work during non-work time at the person level. Psychological detachment from work was positively related to low emotional exhaustion and a high morning recovery state, both at the person and the day level. LMX moderated the relationship between leader support for recovery (overall measure), empathy for recovery, and respect for boundaries on the one hand and psychological detachment on the other hand, such that the relationships became non-significant when LMX was lower. The study suggests that leaders in high-quality relationships can contribute to employee recovery – a process that helps to maintain employee well-being.