In this paper, the author comments two epidemiological studies on the use of condoms with youths between 15 and 18 (H. Lagrange, B. Lhomond, and the ACSJ team) and the risk frequency rate of Aids among the young drug-users (F.Lert). She draws the following conclusions :

– adolescents are responsible subjects who do respond to health messages,

– prevention actions may be useful and efficient,

– however the actions with high-risk youths should be thought over more carefully.