The East Midlands Ambulance Service (EMAS) is an ambulance service formed in April 1999 as a result of the merging of the Derbyshire, Nottinghamshire and Leicestershire (including Rutland) ambulance services. The Ambulance Service NHS Trust covers an area of well over 2,700 square miles, and is headquartered in the City of Nottingham. The Service receives more than 284,000 genuine emergency calls a year. Derbyshire is a county in the East Midlands of England, and boasts some of Englands most attractive scenery. ... Nottinghamshire (abbreviated Notts) is an English county in the East Midlands, which borders South Yorkshire, Lincolnshire, Leicestershire and Derbyshire. ... Leicestershire (abbreviated Leics) is a landlocked county in central England. ... Nottingham is a city (and county town of Nottinghamshire) in the East Midlands of England. ...

On July 1 2006, the EMAS extended its area to cover the East Midland counties of Northants and Lincolnshire, making it one of the, if not the largest NHS Ambulance Service Trust outside of Greater London. ^{[citation needed]} Northamptonshire (abbreviated Northants) is a county in central England with a population of 629,676 (2001 census). ... Lincolnshire (abbreviated Lincs) is a county in the East Midlands of England. ... NHS Ambulance Services Trusts provide ambulance services within the English National Health Service. ... Greater London is the top level administrative subdivision covering London and forms one of the nine regions of England. ...

Previously Northants was served by the Two Shires Ambulance Service NHS Trust, formed as a result of a merger of the Northants and Bucks (Buckinghamshire) ambulance services, however by the start of 2007 Northamptonshire will be served only by the EMAS, while Buckinghamshire is served by the South Central Ambulance Service Oxfordshire-Buckinghamshire branch. Likewise as with Northants, Lincs will be served by the EMAS and the former Lincolnshire Ambulance and Health Transport Service NHS Trust will be done away with.

This means that the East Midlands Ambulance Service will cover all six counties that make up the East Midlands, rather than just three of them, and will serve a number of over 4 million people.