Data. In France, the incidence of type 1 diabetes in children was tracked from 1988 to 1997 in a registry covering 15% of the French population under the age of 20. During this period, the annual rate rose from 7.4 per 100,000 to 9.5 per 100,000. This increase (3.7% per year) persists, and a relevant hospital study estimated this rate at 13.5 in 2004 in Aquitaine. In Europe, incidence rates were measured within a network of similar registries and were found to vary widely across the continent, ranging by a factor of 1 to 8. The lowest rates were in Romania and Greece, the highest in Finland (latest known rate = 60 per 100,000 in 2006) and, curiously, in Sardinia. The increase in rates was 3.2% per year during the 1990s, and even higher among the youngest children aged 0–4 years (4.8%). Implications. The rise in incidence, particularly among very young children, raises the issue of their highly specialized care, which is extremely time-consuming for healthcare staff. Causes. The rapid and recent increase in incidence suggests a role for environmental factors. Infant feeding and enterovirus infections have been cited, but not vaccinations. Nevertheless, no single factor alone explains the rapid increase among young children. To date, no preventive measures have proven effective. (R.A.)