Complaints of chronic understaffing in organizations have become common among workers as employers face increasing pressures to do more with less. Unfortunately, despite its prevalence, there is currently limited research in the literature regarding the nature of workplace understaffing and its consequences. Taking a multilevel approach, this study introduces a new multidimensional conceptualization of subjective work group understaffing, comprising of manpower and expertise understaffing, and examines both its performance and well-being consequences for individual workers (Study 1) and work groups (Study 2). Results show that the relationship between work group understaffing and individual and work group emotional exhaustion is mediated through quantitative workload and role ambiguity for both levels of analysis. Work group understaffing was also related to individual job performance, but not group performance, and this relationship was mediated by role ambiguity. Results were generally similar for the 2 dimensions of understaffing. Implications for theory and research and future research directions are discussed.