The Department of Epidemiology, headed by Dr. Deepa Niranjan, is dedicated to understanding the distribution, determinants, and impact of diabetes and its complications within diverse populations. Since its inception, the department has undertaken several landmark studies, including the Chennai Urban Population Study (CUPS), Chennai Urban Rural Epidemiology Study (CURES), ICMR–India Diabetes (INDIAB) Study, Prospective Urban and Rural Epidemiology (PURE) Study, Chunampet Rural Diabetes Prevention Project (CRDPP), Women in India with GDM Strategy (WINGS), Stratification of Risk of Diabetes in Early Pregnancy (STRiDE), and Precision-CARRS. Through these extensive research initiatives, the department continues to make significant contributions to public health, diabetes prevention, and evidence-based policymaking.