The main impetus came from the late Kelly West's book "Epidemiology of Diabetes and its Vascular Lesions" published in 1978. In addition, World Health Organization and American Diabetes Association Expert Committees made astute recommendations on the classification and criteria for diabetes and associated categories of glucose intolerance as well as methodological issues for diabetes epidemiology studies in diverse populations. These studies have provide direction for research into the possible molecular defect/s and biochemical mechanism/s underlying both Type 1 and 2 diabetes as well as important information on the extrinsic (social, cultural and environmental) risk determinants.