In the fight against HIV-Aids, prevention strategies are a determining stake. Can one however be satisfied with devices that would not be submitted to a critical assessment ? From the point of view of its impact and consequences, prevention must be both at once efficient and respectful of the person in its rights and values. The adolescent should be able to be granted an access to all information allowing him to have a series of autonomous choices at hand and which also would enable him to stress his own responsibilities whereas at the same time his frailties would be taken into account.