The transitional period from adolescence into adulthood is an important developmental stage, known to be a risk factor for mental health problems. Neuropsychiatric disorders are the main cause of disability for young people aged 10–24 years and they seem to precede mental health disorders in adults. Since persistence of an adolescent episode is a strong predictor of outcome, giving proper care during critical stages might prevent later life psychiatric morbidity arising from adolescent-onset disorders. Mental health services for adolescents have evolved from non-specific secondary treatment to more extensive treatment goals, where prevention and early diagnosis take place; at the same time, specific therapeutic tools for adolescents are increasing and put into practice. In Europe, both child and adolescent psychiatrists (CAP) and adult psychiatrists treat adolescents, and for a few countries, the specialty of adolescent psychiatry exists. In this symposium, we propose to address new strategies to treat adolescents with defying pathologies that often pose problems; we will do it through the scope of CAP and adult psychiatry.