<p>The necessity for a&#xa0;well-prepared and sustainable transition to adult care is evident, especially for adolescents with complex diseases. For the field of endocrinology this particularly involves the transfer in cases of hypothalamic-pituitary dysfunction, diseases of the adrenal and thyroid glands, disorders of glucose metabolism as well as rare genetically linked syndromes with associated endocrinopathies, hereditary disorders of bone metabolism and tumor predisposition syndromes. These often belong to the so-called group of rare diseases and necessitate a high level of specialized multidisciplinary care over the entire lifespan. The main priorities are age-specific and sex-specific aspects as well as various individual aspects that can develop during the course of the disease. The treatment targets also change during the period of transition from adolescence to adulthood. It has been shown that a joint accompaniment of adolescents and young adults by pediatricians and specialists in internal medicine throughout the complete individually adapted transition process has positive effects on the establishment of an adequate long-term medical treatment situation of the patients. This is a prerequisite for a reduction of morbidity and mortality as well as improvement of the quality of life. The demands on specialized outpatient transition in the field of hormone and metabolic diseases are very high and necessitate a close cooperation between the pediatric and internal medical teams. This can only permanently and comprehensively succeed when sufficient personnel and infrastructural support are available in order to implement the necessary multidisciplinary and interprofessional care for the optimal treatment and management of patients with chronic and mostly rare and complex diseases.</p>