Leonard Colebrook was born on 2 March 1883, son of May Colebrook and his wife Mary Gower, and was educated at three schools: Guildford Grammar School, The High School at Eastbourne, and Christ's College at Blackheath. He was admitted as a student to St Mary's Hospital Medical School during the South African war in 1900 and qualified as a doctor in 1906. He was attracted to that remarkable intellect, Sir Almroth Wright, and he was one of the group of brilliant disciples of this great man which included Sir Alexander Fleming, Major Douglas, John Freeman, John Matthews ("honest John"), R M Fry, Ronald Hare, A B Porteous "Proteus", and many others who became famous in their time. He was greatly attached to Almroth Wright, went with him to Boulogne in the first world war and worked with him in the old casino there. He advocated for war-wounds of that war, not to use antiseptics, but to use the inborn powers of nature to overcome the septic wounds by means of the patient's own resistance, using only hypertonics such as hypertonic saline or magnesium sulphate to draw the patient's own bactericidal serum into the wound, holding that antiseptics did more harm to the patient and his tissues than they did to the germs causing the sepsis. This was sound advice at the time, awaiting the discovery of an antiseptic which would kill the germs without harming the host. This was discovered by Domagk in Germany in 1932, twelve years after Colebrook had returned to St Mary's with Almroth Wright. His great work with Sir Almroth secured his appointment to Queen Charlotte's Hospital in 1930, and during this time he used 'Prontosil' and later its key substance sulphonamide in the treatment of puerperal sepsis and his work brought this disease to an end. It was a triumph of therapeusis ranking with Lister's in 1867, and he can be regarded as having achieved one of the greatest advances in therapeutics which has probably saved a million lives since it was discovered. When the second world war came in 1939 he again entered the Army as a Colonel at the age of 56, became bacteriologist to the Army in France and introduced the dusting of wounds with sterile sulphonamide powder, which caused sepsis almost to vanish. This was his second great contribution to medicine and surgery. His third great contribution came after his return from France in 1940, when he joined a team at the Medical Research Council and worked on the septic element in burns and scalds, and helped to produce their well known Special Report No 240 in 1945. Following this he organised the burns unit at the Accident Hospital at Birmingham. Possibly the tedious course of his burns patients' cure led Colebrook to his great campaign for the prevention of burns by measures such as screening fires and non-inflammable clothing. As a student he was a diffident and little known person. He was tremendously keen on games, but he would always be seen sitting shyly by himself and little known to other players because he was almost always 'twelfth man'. So he remained, quiet and self-effacing all through his life, during which he never lost his devotion to his great master Sir Almroth Wright whose biography he published in 1954, an admiring and loving book about a most remarkable man. Honours in many came to him in due course: Honorary FRCOG in 1944, FRS in 1945, FRCS and Honorary DSc of Birmingham University in 1950. The Blair Bell Medal was presented to him in 1955, and in 1962 the Royal Society of Medicine gave him their Jenner Medal. Colebrook was twice married, first in 1914 to Dorothy Scarlett Campbell, and secondly in 1946 to Vera Scovell. There were no children of either marriage. He never changed from the shy student of the 1900s, and his husky endearing voice and furtive smile was long remembered by all who knew this remarkable man, always self-effacing but a real and lovable genius. As the years pass his medical stature will grow when men remember his conquest of the poignant disease puerperal sepsis, his overcoming of sepsis in wounds by sulphonamide dusting, and his great efforts to reduce the horror and the incidence of burns. To his intimate friends he was always known as "Coli" just as his great friend and colleague Porteous was known as "Proteus". Others may remember him as "Elsie" (from his initials LC), with which name he would sign presentation copies of his great life of his dear friend and master Almroth Wright. He died on 29 September 1967 aged 84. Publications: Prontosil in puerperal infection. *Lancet*, 1936,1, 1289, 1300, 1441. *The prevention of puerperal sepsis*. 1936. *A new approach to the treatment of burns and scalds*. 1950.