There have been substantial increases in all categories of professional manpower in the National Health Service since it was first established in 1949. This Briefing examines and discusses the trends for doctors, nurses and midwives. The data it presents relate mainly to England, but similar trends apply to Great Britain as a whole. The discussion draws attention to the balance in professional manpower between hospitals and the domiciliary services. It also attempts to relate the growth in manpower to measures of medical activity, and emphasises the need for further studies to examine more critically this relationship.