In August 1948, WHO undertook an investigation of the medical aspects of delinquency. Dr. Lucien Bovet, appointed as WHO's consultant, visited 60 institutions in Europe and the United States, consulted with over 150 specialists, and produced a monograph on the psychiatric aspects of juvenile delinquency. The report contained several recommendations, such as systematically gathering statistics on juvenile delinquency and establishing a delinquency research budget that would be proportional to the total amount spent by a country for the management of delinquents. Dr. Bovet advocated outpatient examination of all juvenile delinquents prior to residential placement. Reports by Dr. Manfred Guttmacher, prepared for WHO in 1949, dealt with adult offenders, with special attention given to (1) the causes and prevention of crime and the treatment of offenders and (2) a plan for the psychiatric examination of offenders prior to sentencing. Also discussed are findings on WHO research on alcohol problems and crime, the 'predelinquent' juvenile, facilities for treatment, and the psychiatric treatment of offenders. Other research papers reviewed focus on trends in juvenile delinquency, deprivation of maternal care, delinquency in Africa, health and social defense planning, and problems of deviant social behavior viewed from the perspectives of both criminologists and psychiatrists. Footnotes are given.