Diabetes mellitus type1 requires lifelong insulin substitution, aiming at near normal glycaemia. Insufficient metabolic control (HbA1c > 8 %) leads to micro and macro- vascular complications. Especially in adolescence a lack of compliance leads to deteriorated metabolic control. Motivational factors play a pivotal role in this age-group, however they have neither been studied so far nor considered in interventions with diabetes patients.