This study analyzed trends in patient safety events over time in the Veterans Affairs (VA) health care system by comparing the rates of Patient Safety Indicators (PSIs) between 2001 and 2004 at all VA inpatient facilities. This study builds on prior research that validated use of PSIs in the VA system. The risk-adjusted rates of most PSIs remained stable over time, with the only increase noted in rates of iatrogenic pneumothorax. Hospital's baseline performance was the strongest predictive factor for future PSI rates; in contrast with a prior study, there was no relationship between the level of quality improvement efforts at an individual hospital and its PSI rate. The authors discuss the potential use of these findings for evaluating patient safety efforts within the VA system.