Aims: To evaluate a 5-day self-management education course for young people with Type 1 diabetes and assess its effects on knowledge, self-efficacy, beliefs, distress, self-management behaviours and HbA 1c. Methods: This is an evaluation of a structured education course. Young people (aged 16–24 years) with Type 1 diabetes were recruited from three diabetes centres. In the first centre, participants completed self-report measures of knowledge, self-efficacy, positive and negative outcome expectancies, and hypoglycaemic worries at baseline (n=47) and the end of the course (n=42). In two additional centres, participants completed these and other measures assessing self-management behaviours, cognitive adaptation to diabetes and diabetes distress at baseline (n=32), the end of the course (n=27) and 3-month follow-up (n = 27). HbA 1c levels were recorded at baseline (n=79), 6 months (n=77) and 12 months (n=65). Results: There were statistically significant increases in self-report knowledge, self-efficacy, positive outcome expectancies and self-management behaviours, and a statistically significant decrease in negative outcome expectances, between baseline and the end of the course. There were also statistically significant increases in self-report knowledge, self-efficacy, self-management behaviours and cognitive adaptation to diabetes between baseline and 3-month follow-up. Compared with baseline, HbA 1c levels decreased by a mean (sd) of 5.44 (19.93) mmol/mol (0.48%) at 6 months (P=0.019), and by 5.98 (23.32) mmol/mol (0.54%) at 12 months (P =0.043). Discussion: The results indicate the potential benefits of a self-management course designed to address the developmental needs and challenges faced by young people with Type 1 diabetes. Further studies with larger numbers and appropriate controls are required to confirm these initial findings.