Fibrocalculous pancreatic diabetes (FCPD) is a unique form of diabetes secondary to chronic pancreatitis seen in developing countries of the world associated with either overt protein-calorie malnutrition or, more likely, with deficiency of certain micronutrients. FCPD affects young individuals and runs an aggressive course to reach the endpoints of diabetes, pancreatic calculi and exocrine pancreatic dysfunction (steatorrhoea) in the majority of cases. There are characteristic features of FCPD radiologically, ultrasonographically, on endoscopic retrograde cholangiopancreatography and on histopathology which distinguish it from chronic pancreatitis of other aetiologies seen in temperate zones, e.g. alcoholic chronic pancreatitis. Although a secondary form of diabetes, specific diabetes-related complications like retinopathy and nephropathy do occur in FCPD. There appears to be a high risk of developing pancreatic carcinoma. Although the aetiology of FCPD is still unclear, the role of micronutrient (antioxidant) deficiency is emerging as a possible aetiological or predisposing factor. The contribution of genetic factors and environmental toxins, e.g. cyanogenic glycosides or other nutritional/toxic factors, merit further study. Studies on FCPD, a good model of a secondary form of diabetes, could lead to improved understanding of other primary forms of diabetes as well. If the underlying aetiological factors are identified, it may also be possible to prevent this type of diabetes.