In 2002, with the support of the Juvenile Diabetes Research Foundation (JDRF), a Clinical Center infrastructure has been created at San Raffaele to host a TrialNet Center. TrialNet is a NIH-supported network of clinical centres, investigators and core support facilities in the US and Canada, United Kingdom, Italy, Germany, Finland and Australia. The goals of TrialNet programs are to: further define epidemiology, natural history and risk factors of type 1 diabetes; support the development and implementation of clinical trials of agents to slow the progression of type 1 diabetes in new-onset patients, and delaying or preventing the emergence of type 1 diabetes in individuals found to be at risk of the disease. Recently completed studies at the San Raffaele Centre include: the metabolic assessment of residual insulin secretion in patients with type 1 diabetes and the Mycophenolate/Daclizumab clinical trial in recent onset patients; ongoing studies include: the natural history of development of type 1 diabetes; studies under implementation include: Oral Insulin for the prevention of diabetes in relatives at risk. An additional focus of the Clinical centre is the creation and expansion of a wide network of affiliate and satellite centres throughout Italy to support the enrolment into all the TrialNet studies. Based on the same JDRF-funded infrastructure, other clinical trials, in addition to those performed within TrialNet, are expected to be developed in the future, possibly including also phase I/proof-of-concept studies.