This position statement with accompanying resource document is the result of a collaborative effort of a writing group comprised of members of the Air Medical Physician Association (AMPA), the American College of Emergency Physicians (ACEP), the National Association of EMS Physicians (NAEMSP), and the American Academy of Emergency Medicine (AAEM). This document has been jointly approved by the boards of all four organizations. Patients benefit from the appropriate utilization of helicopter emergency medical services (HEMS). EMS and regional health care systems must have and follow guidelines for HEMS utilization to facilitate proper patient selection and ensure clinical benefit. Clinical benefit can be provided by Meaningfully shortening the time to delivery of definitive care to patients with time-sensitive medical conditions Providing necessary specialized medical expertise or equipment to patients before and/or during transport Providing transport to patients inaccessible by other means of transport The decision to use HEMS is a medical decision, separate from the aviation determination whether a transport can be completed safely. Physicians with specialized training and experience in EMS and air medical transport must be integral to HEMS utilization decisions, including guideline development and quality improvement activities. Safety management systems must be developed, adopted, and adhered to by air medical operators when making decisions to accept and continue every HEMS transport. HEMS must be fully integrated within the local, regional, and state emergency health care systems. HEMS programs cannot operate independently of the surrounding health care environment. The EMS and health care systems must be involved in the determination of the number of HEMS assets necessary to provide appropriate coverage for their region. Excessive resources may lead to competitive practices that can affect utilization and negatively impact safety. Inadequate resources will delay receipt of definitive care. National guidelines for appropriate utilization of HEMS must be developed. These guidelines should be national in scope yet allow local, regional, and state implementation. A National HEMS Agenda for the Future should be developed to address HEMS utilization and availability and to identify and support a research strategy for ongoing, evidence-based refinement of utilization guidelines.