The critical role that nurses play in ensuring patient safety can be compromised by excess workload. A large body of literature has linked higher patient-to-nurse ratios to a variety of preventable complications and even increased inpatient mortality. However, it is not clear whether high nursing workload alone can impair patient safety, or if overall working conditions for nurses also plays a role in safety. This study, which examined the association between hospital-acquired infections, nurse staffing, and burnout among nurses found that the number of patients per nurse did not entirely predict safety problems. On the other hand, after controlling for hospital and patient characteristics, the investigators found that increased rates of burnout among nurses was significantly associated with a higher risk of hospital-acquired infections. The complex issue of nurse staffing and workload is discussed in this AHRQ WebM&M commentary.