ssue 21 of Cooperative Approaches was published in partnership with two major youth organizations in France: Scouts et Guides de France and UCPA (Union des Centres de Plein Air). It addresses a crucial topic: adolescent mental health. Adolescents face all the challenges and anxieties of the transition from childhood to adulthood, and their mental health is often at risk. This issue gives a voice to educators and psychologists who explain the difficulties young people encounter and how to deal with them. It then presents several initiatives developed by citizens or public authorities to support young people in this difficult phase.