This book is intended to be a general guide to sex education for children. The point of view is that generally accepted in mental hygiene. It is written in an easily understandable manner. The terminology is not too difficult for the laity. Sex is described as a primary emotional impulse. It is discussed from birth through adolescence. The everyday problems met at various levels of development are discussed. There is emphasis on sex questions that arise in handling children. The material was gathered from many years of observation and experience with children. The book is interesting, concise and scientific. While the conclusion and general principles are not new, the method of approach to the problem is interesting, practical and thorough.