The transition from adolescence to adulthood represents a major developmental challenge for every-one; while it often succeeds, it sometimes fails or threatens to fail. As adolescence and young adulthood represent a particularly vulnerable period for the development and chronification of mental disorders, the best possible care needs to be ensured for these age groups. The necessary transition from adolescent-centred to adult-oriented care represents an additional challenge as regards development related aspects. During this period, the specific needs of mentally ill adolescents aged between 16 and 24, all of whom have different maturational processes and developmental conditions, need to be considered. The psychiatric help system is faced with the challenge of organising this transition in an optimal manner and supporting the adolescents in solving related problems. At present, however, in many areas there are still considerable problems at the interface between the different segments of care in childhood, adolescence and adulthood, resulting in higher treatment discontinuation rates, treatment disruptions and other factors that have a negative impact on the course and prognosis.
Although the transitions between developmental stages differ greatly between individuals, sharp boundaries or transition periods are formally defined for the transition from adolescence to adulthood. Young people reach the age of majority on their 18th birthday. In the night before their 18th birthday, issues of self determination and treatment consent change fundamentally. Nevertheless, in various contexts, the legislator provides criteria for individual maturity. Thus, in Germany, adolescents aged 14 or 15 may be able to give consent if they can fully grasp the consequences of respective decisions. In German criminal law, a specific category exists for juveniles (18-21 years) which allows juvenile law to be applied to young adults if certain immaturity criteria are fulfilled. Youth welfare social law provides assistance with the education and integration of psychiatrically disabled young people or young people at risk of psychiatric disability until age 21, in exceptional cases even up to age 27. If adolescents are considerably behind in maturity, after the age of 18, legal care can be ar-ranged and is often further delegated to parents.
As a result of the reform of participation support and integration assistance and the upcoming partic-ipation legislation for adults as well as children and adolescents, this age limit – which is relevant for the complementary care of many young people with mental health problems – has to be redefined and redesigned in the respective service areas.
Maturation processes are rarely linear. Rather, particularly in young people with mental illness, one can sometimes observe developmental setbacks or strong efforts at independence. As regards devel-opmental psychology, international data (see Seiffge-Krenke 2015) show an increasing...