St John Ambulance, branded as St John in some territories, is a common name used by a number of affiliated organisations in different countries dedicated to the teaching and practice of medical first aid

First aid

First aid is the provision of initial care for an illness or injury. It is usually performed by non-expert, but trained personnel to a sick or injured person until definitive medical treatment can be accessed. Certain self-limiting illnesses or minor injuries may not require further medical care...

 and the provision of ambulance

Ambulance

An ambulance is a vehicle for transportation of sick or injured people to, from or between places of treatment for an illness or injury, and in some instances will also provide out of hospital medical care to the patient...

 services, all of which derive their origins from the St John Ambulance Association founded in 1877 in the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

. Each national group falls within the charge of a Priory or National Council of the Venerable Order of Saint John

Venerable Order of Saint John

The Most Venerable Order of the Hospital of Saint John of Jerusalem , is a royal order of chivalry established in 1831 and found today throughout the Commonwealth of Nations, Hong Kong, Ireland and the United States of America, with the world-wide mission "to prevent and relieve sickness and...

 in which each Priory ranks alongside the others.

In several priories St John Ambulance has commercial sections or subsidiaries operating to generate surplus for charitable activities; these are structured much like other commercial bodies.