Federal funding provides state public and private health care systems the ability to build and maintain a reserve supply of ventilators for emergency response to mass casualty incidents. Studying and planning the ventilator reserve capability requires subject-matter expertise, identification of best mechanical-ventilation practices and quality care standards, and contingency planning. Natural disasters such as pandemic influenza, or man-made disasters such as bioterrorism could necessitate field use of numerous mechanical ventilators. This paper discusses the pros and cons of stockpiling ventilators at one site (to be distributed as needed to disaster areas) versus increasing the number of ventilators at all hospitals. Respiratory-device corporations, respiratory professional associations, and respiratory therapists should be involved in the planning and development of respiratory mass casualty response systems.