Type 2 diabetes and impaired glucose tolerance are an increasing burden not only for affected patients, but also for the whole health care system. The pathophysiology of diabetes and its late complications are far from being understood with hyperglycaemia being only the last sign of a long lasting and complex metabolic dysfunction. One major problem in finding therapeutic targets is the fact that the cellular disorders responsible for the development of diabetes involve phylogenetically ancient repair mechanisms. This is one of the reasons why therapeutic targeting of these mechanisms is difficult with the exception of life-style interventions which are, however, limited by individual compliance. In addition, the impact of many therapeutic agents on the entire organism is not well understood. Blood glucose control cannot be considered "high tech" medicine and requires non-medical personnel to reach defined blood glucose targets. Non-adherence to treatment and life-style changes, however, facilitate the interaction of patients and medical personnel and individuals with diabetes are therefore often considered themselves to "blame" for being affected by diabetes. Finally, generating treatment guidelines is extremely difficult as clinical studies targeting vascular endpoints need more than 10 years to become informative, partly due to the so-called glycaemic memory.