In contrast to adults Diabetes mellitus type 1 (DMT1) is the most frequent form of diabetes mellitus during childhood and adolescence (> 95 %). After diagnosis, the management of these DMT1-patients should take place in specialized paediatric centres, not in a primary care setting. The lifelong substitution of insulin is the cornerstone of therapy, the form of insulin-therapy should be adapted according to the age of the patient (conventional, intensified or pump therapy). Diabetes education is also an essential part in the management of diabetes patients and their families. The ISPAD (International Society for Paediatric and Adolescent Diabetes) recommends an HbA1c < 7.5 rel.%(IFCC < 58 mmol/mol) as good metabolic control, although it might be difficult to achieve this goal during different phases of life (e.g. toddlers or puberty). The aim of diabetes education and management is avoidance of acute and late diabetes related complications, as well as achievement of normal growth and psychosocial development and wellbeing.