The development of Helicopter EMS (HEMS, or as the Federal Aviation Administration recently coined it: “Helicopter Air Ambulance” or “HAA”) services in the United States has taken a decidedly different path in recent years compared to those in other countries. The wide spread use of single engine, VFR only aircraft, owned and operated by for profit companies is a uniquely American phenomena; at odds with most other countries who have developed HEMS programs around the world. This has resulted in significant direct competition between HEMS programs, as well as highly questionable billing practices that have started to garner attention. The origins of this development, including the use of the US “Airline Deregulation Act” to prevent states from regulating HEMS programs will be examined. More recent efforts in the US to tie reimbursement and program accreditation to the levels of care provided and minimum standards of equipment are still nascent at this time. Efforts by the US National Transportation Safety Board (NTSB) to mandate improved safety equipment standards have been met with resistance by the industry and the FAA. This has resulted in wide variability in US HEMS programs and the adoption of IFR standards, mandating NVG use, twin-engine aircraft and risk assessment strategies. There is also increasing scrutiny being placed on appropriate utilization criteria in the face of skyrocketing bills and questionable billing practices by for-profit companies.