During the past 10 years, it has become clear that adolescence is a crucial time for the acquisition of behaviours that will favour good overall health. Indeed, the more adolescents who are able to make favourable decisions regarding their health, the more effective a prevention policy we will have for a number of diseases and illnesses (cardiovascular, psychiatric, cancer, etc.). The specialist's goal is to have the young person assume more responsibility for his or her health. Such a goal should take into account a number of factors specific to this age group. Accordingly, adolescents should not be thought of simply as miniature adults. If disease is defined in the adult as a loss of good health, it is defined as a problem in the development of good health during adolescence. At this age, the state of one's health can be attributed, in part, to various adolescent stresses such as family relationships, depressive experiences, and behaviours that include experimentation with drugs. A health care professional must be able to take all of these factors into account. This book gives a voice to the various specialists who encourage this particular way of thinking when approaching adolescents and their health.