Type 1 diabetes (T1D) is the most common metabolic disease in childhood with an increasing incidence of about 3 to 5% per year, particularly in preschool children. Despite substantial progresses in diabetes research concerning its pathogenesis and etiology in the last decades, there is no strategy for primary prevention in subjects with subclinical signs of diabetes. Nowadays, it is well-known that T1D is caused by partial or total destruction of pancreatic islet cells, resulting in progressive incapacity to produce insulin. This inflammation is of an autoimmune nature, resulting both from environmental and genetic influences. Children with T1D usually have a several day history of typical symptoms such as frequent urination, excessive thirst and weight loss, which appear when about 80% of the pancreatic beta cells are already destroyed. If those symptoms are misinterpreted, the continuing hyperglycaemic metabolism leads to a potential life-threatening condition the diabetic ketoacidosis. Patients with T1D require daily subcutaneous injections of insulin, with the overall aim to mimic the physiological release of insulin during meal-associated and fasting periods (intensive insulin therapy). The most important parameters to evaluate the effectiveness of insulin treatment are blood glucose monitoring and HbA1c. The increased availability of systems for continuous glucose monitoring may help patients to have a better insight into their metabolic conditions. Sensor-based insulin treatment is likely to have a significant impact on paediatric diabetes therapy and education in the future.