Emergency medical services (EMS), also known as ambulance services or paramedic services, are emergency services that provide urgent pre-hospital treatment and stabilisation for serious illness and injuries and transport to definitive care. They may also be known as a first aid squad, FAST squad, emergency squad, ambulance squad, ambulance corps, life squad or by other initialisms such as EMAS or EMARS.
In most places, EMS can be summoned by members of the public (as well as medical facilities, other emergency services, businesses and authorities) via an emergency telephone number (such as 911 in the United States) which puts them in contact with a dispatching centre, which will then dispatch suitable resources for the call. Ambulances are the primary vehicles for delivering EMS, though squad cars, motorcycles, aircraft, boats, fire apparatus, and others may be used. EMS agencies may also operate a non-emergency patient transport service, and some have rescue squads to provide technical rescue or search and rescue services.
When EMS is dispatched, they will initiate medical care upon arrival on scene. If it is deemed necessary or a patient requests transport, the unit is then tasked with transferring the patient to the next point of care, typically an emergency department of a hospital. Historically, ambulances only transported patients to care, and this remains the case in parts of the developing world. The term "emergency medical service" was popularised when these services began to emphasise emergency treatment at the scene. In some countries, a substantial portion of EMS calls do not result in a patient being taken to hospital.
Training and qualification levels for members and employees of emergency medical services vary widely throughout the world. In some systems, members may be present who are qualified only to drive ambulances, with no medical training. In contrast, most systems have personnel who retain at least basic first aid certifications, such as basic life support (BLS). In English-speaking countries, they are known as emergency medical technicians (EMTs) and paramedics, with the latter having additional training such as advanced life support (ALS) skills. Physicians and nurses may also provide pre-hospital care to varying degrees in certain countries, a model which is popular in Europe.