Increasing numbers of children and adolescents are developing type 2 diabetes. Symptoms of this condition include obesity, a sedentary lifestyle, insulin resistance and hypertension. Type 2 diabetes is more common in girls and families with a positive history of the disease. Diagnosis is often delayed and may identify the presence of chronic complications. An oral glucose tolerance test and a two-hour plasma glucose assessment are the best screening and diagnostic investigations. Treatment is based on weight reduction with diet and exercise, glycaemia monitoring and medication if necessary.