Using principles from conservation of resources theory (Hobfoll, 1989), this study examined the time-lagged relationship between perceived organizational support (POS; measured at Time 1), emotional exhaustion (measured 6 months later), and turnover (measured 1 year after Time 1), and included negative affectivity (NA) as a moderator. Drawing on a sample of employees from multiple organizations (N = 135), we found POS to be unrelated to emotional exhaustion but the latter to be negatively related to turnover. NA moderated the relationship between POS and emotional exhaustion and POS’s indirect relationship to turnover, these relationships being stronger and positive at high levels of NA. Moreover, NA moderated the link between emotional exhaustion and turnover, this link being stronger and positive when NA was low. We discuss the relevance of conservation of resource theory as a useful framework for interpreting POS’s effects.