Depending on the definition of this concept that is adopted, adolescence is the narrow threshold or a vast no-man's land that separates adulthood from childhood. In one -physica1ist- view, adolescence begins when secondary sex characters become noticeable and ends when they are fully developed. In another -socio1ogica1- view, adolescence ends when social independence has been gained. It may easily take many years more to span the interval between those two events. In this collection of papers by specialists from various disciplines, physical, psychological and social aspects of adolescence are considered. The book originates from a postgraduate course for medical practitioners, who deal with adolescents, but the range of the papers is such that we hope it may be of value to a much wider readership, including educators and all who are concerned with adolescents. The course was entitled: 'Adolescence: psychological, social and biological aspects', and was held in Leiden in November 1981. It was the fourth in a series of Boerhaave Courses instigated by the Dutch Growth Foundation of available. which a published record has now become Previous titles are 'Somatic growth of the child' (1966), 'De samenstel1ing van het mense1ijk 1ichaam' (1968) (=Human body composition), and 'Normal and abnormal development of brain and behaviour' (1971). VI The detailed programme of the course was planned by Dr. F.J. Bekker, Prof. Dr. J.L. van den Brande, Prof. Dr. W. Everaerd, Prof. A.Th. Schweizer and Prof. Dr. J.J. van der Werff ten Bosch.

A historical and transcultural view of adolescence.- Concepts of adolescence; their applicability to normal and clinical samples.- Psychological changes in adolescence related to physical changes.- The psychobiology of developmental behavior disorders.- Influence of early exposure to steroid hormones on behavioral development.- The effects of a chronic illness on somatic growth and psychological development.- Adolescents and family disruption through marital separation.- Erotic overtures and sexual contacts; competence, rules, attitudes and problems.- Sex roles and coping with emotions.- Outpatient social skills training for youth in trouble; theoretical background, practice and outcome.- The implementation and evaluation of a residential social skills training program for youth in trouble.- Suicidal behaviour among adolescents.- How are we to deal with adolescents and their problems?.- Epidemiology and the role of public health organizations.