Despite a recent strengthening of the registered nurse (RN) workforce, the US health care delivery system needs to prepare for an aging population of RNs and a coming wave of retirements. Over the next 20 years, the average age of RNs will increase, and the size of the workforce will plateau as large numbers of RNs retire.1 Because the demand for RNs is expected to increase steadily during this same period, a large and prolonged shortage of RNs is expected to develop in the latter half of the next decade, threatening access and quality and increasing health care costs. The question looming over the nursing profession, employers, nursing educators, physicians, other health professionals, and health care policy makers is what can be done to mitigate these developments.