both the Middlesex Hospital and the Great Ormond Street Hospital as physician. All the appointments were interrupted by the World War II, when he worked at the Emergency Medical Service. After the war, when the Institute of Child Health was founded at the Great Ormond Street Hospital in 1946, Moncrieff was appointed first Nuffield Chair of Child Health at the University of London and Director of the institute, a position he held until 1964, which was based across the hospitals, Queen Elizabeth Hospital for Children, Hackney, the Royal Postgraduate Medical School, Hammersmith, and at Great Ormond Street. Neonatal problems remained a lifelong interest for him, as shown by his development in 1947 of the premature baby unit that was one of the first units of its type and became the foremost of its kind in London. This unit was incorporated into the Institute of Child Health. Over the next several years, the institute was developed by Moncrieff, into an organisation of postgraduate paediatric teaching at the beginning, in co-operation with the Institute of Education, in developing a department of growth and development. Frank Falkner was responsible for this department from 1953 onwards, followed by James Mourilyan Tanner. In 1946, he played a prominent part in establishing the National Prenatal Mortality Survey, which would later lead to the National Child Development Study. It was Moncrieff more than anybody else, who established preventative and social paediatrics with Europe. The next few years were spent assisting in the organisation of child health services in Hertfordshire, where he lived, and in continuing his work on phenylketonuria, until he suffered a stroke in 1968 and has to drastically reduce is working habits. External work During his long career, Moncrieff worked on several Home Office and Ministry of Health committees. One of the most prominent was the central training council in childcare. He worked in advisory capacity on the Ingleby committee for children and young people. He provided expert advice for the formation of the Children's Act 1948 which laid the foundations of social care of children and young people by local authorities, in those instances when the child was without parents or whose parents could not look after them. He has a position at the Medical Research Council, as an expert advisor, on the clinical research board. He acted on the expert advisory panel on maternal and child health panel. of the World Health Organization