Although the main value of hospital statistics is administrative, in connection with planning future needs of the mentally ill, they have been used by Shepherd (1957a), Brown et al. (1961), Barr et al. (1962), and Ratcliff (1964) to study trends in the characteristics and fate of patients admitted to mental hospitals. Since the factors that govern the admission of patients to psychiatric hospitals are both complex and varied, as has been shown by Svendsen (quoted by Reid, 1960), it would be more correct to say that the studies referred to describe the end-results of a number of factors interacting with each other and changing from time to time, such as hospital policy, demands of the mentally ill, available resources, therapeutic advances, attitudes of the community to admission, the state of the law, and so on. All these factors could be expected to influence the number and characteristics of patients admitted, especially for the first time.