St Mary's Hospital is an NHS hospital in Paddington, in the City of Westminster, London, founded in 1845. Since the UK's first academic health science centre was created in 2008, it has been operated by Imperial College Healthcare NHS Trust, which also operates Charing Cross Hospital, Hammersmith Hospital, Queen Charlotte's and Chelsea Hospital, and Western Eye Hospital.
Until 1988 the hospital ran St Mary's Hospital Medical School, part of the federal University of London. In 1988 it merged with Imperial College London, and then with Charing Cross and Westminster Medical School in 1997 to form Imperial College School of Medicine. In 2007 Imperial College became an independent institution when it withdrew from the University of London.
St Mary's Hospital first opened its doors to patients in 1851, the last of the great voluntary hospitals to be founded.
With the shift towards community healthcare delivered in the early 20th century, partly due to the social medicine revolution, pressure on bed occupancy relaxed, and with the formation of the National Health Service in the 1940s, many of the local hospitals of the St Mary's teaching hospital group eventually closed and relocated services to the Paddington basin site:
St Charles' Hospital, formerly the Marylebone Workhouse Infirmary, and the Western Eye Hospital, formerly the Western Ophthalmic Hospital, remained as part of the St Mary's Hospital NHS Trust, now all part of Imperial College Healthcare NHS Trust.
The hospital site incorporates the private Lindo wing where several celebrity and royal births have occurred. The wing is named after Frank Charles Lindo, a businessman and board-member of the hospital, who donated £111,500 before his death in 1938.
The laboratory where Alexander Fleming discovered penicillin has been restored to its cramped condition of 1928 and incorporated into a museum about the discovery and his life and work. The museum is open to the public from Monday to Thursday from 10am to 1pm and can be visited by appointment outside of these times. The museum is a member of the London Museums of Health & Medicine.
St Mary's Hospital is located beside London Paddington railway station, the principal station of the Great Western Railway and its successors. In celebration of the association, a British Rail Class 43 (HST) locomotive (number 43 142) was named "St Mary's Hospital, Paddington" on 4 November 1986. The locomotive is still in service but, following changes of ownership, the name has now been removed. One of the large metal nameplates was acquired by the hospital, and is now displayed in the foyer of the Cambridge Wing.
St Mary's Hospital is one of four major trauma centres in London. The other three are: King's College Hospital in Denmark Hill, The Royal London Hospital in Whitechapel, and St George's Hospital in Tooting.