Adolescents need psychiatric care more often than children. About 20-30% of adolescents have psychiatric problems. Comorbidity is common; e.g. depression and symptoms of anxiety are often concomitant. Most mental problems that threaten the functional ability of adults begin in adolescence at about the age of 16.Early intervention and low threshold to treatment are essential when encountering adolescents with mental problems.The prevalence of mental problems in adolescence is so high that even in well-organized health care systems 40-60% of young persons are left without treatment that they need.