This article describes the high prevalence of maturity-onset diabetes in the young (MODY) in an Indian clinic population of diabetic patients. MODY appears to be more common among Indians than among Caucasians. Only 27% of MODY patients had definite autosomal-dominant inheritance. In 73% the mode of inheritance was not definite. Microvascular complications were common and macrovascular complications rare. The high prevalence of MODY in this diabetes clinic might suggest an ethnic variation in diabetes.