The author reviews the causes of nursing shortages and surpluses and examines data from California hospitals to demonstrate how these cycles are expressed in the demand for and wages of nurses. Nursing shortages have been reported cyclically for more than 50 years in the United States. There has been little data analysis demonstrating the relationship between the current shortage and changes in wages and nurse staffing. Longitudinal hospital and patient data from the California Office of Statewide Health Planning and Development were analyzed. Summary statistics of patient utilization, nurse staffing, and nurse wages were computed. The data demonstrate that cyclical shortages are accompanied by higher wages and employment. This has been true in recent years. However, in medical–surgical units, hours per patient day declined between 2001 and 2002, perhaps reflecting the inability of hospitals to find more nurses to meet staffing goals. Nurse staffing per patient day and per discharge have remained stable, despite concerns about low staffing levels. Improved measures of patient care needs and studies of the precise staffing requirements for different types of patients and configurations of staff are required to make recommendations about staffing and policy.