Briefly, cord blood samples are collected and HLA-DR-DQ genotypes are determined from newborn babies. Families with a newborn baby carrying a DR-DQ genotype associated with increased risk for T1D are invited to participate in regular follow-up at the age of 3, 6, 9, 12, 18 and 24 months, and thereafter once a year until the age of 15 years or until T1D is diagnosed. Clinical details including maternal diet during pregnancy and lactation and child's diet starting from the age of 3 months are recorded, blood samples are collected, and serum autoantibodies associated with development of T1D are measured. Children who develop beta-cell specific autoimmunity are followed more intensively with measurements of glucose metabolism parameters such as glycated haemoglobin A1c (HbA1c), oral glucose tolerance tests (OGTT) and intravenous glucose tolerance tests (IVGTT). In the DIPP Study more than 1000 children have developed multiple islet autoantibodies and more than 450 of these have progressed to clinical T1D. It has been estimated that 5% of children in the follow-up will develop T1D and 60% of future T1D cases will be reached by the current screening and follow-up strategy.