This article describes the aims of sex education; to inform, to allow the adolescent to understand his body changes, and the expression of his own sexuality, and finally to develop his ability to make responsible decisions in the area of affective and sexual life. In view of the changes in attitudes and behavior among adolescents over the last 20 years, different countries have developed several sex education programs. This paper deals with the many aspects of such programs; who should teach it, when, where, and how it should be taught. The evaluation of such programs is duscussed. The role of doctors is important in this area and a practical approach is described. (author's)