... Emerging data, largely from the diaspora and largely cross-sectional, indicate that South Asians exhibit high rates of cardiovascular disease (CVD), diabetes, atypical dyslipidaemia profiles, and hepatic steatosis1–7 at lower body weight and younger ages relative to populations with European and other ancestries.8–10 It is hypothesized that these differences are rooted in some combination of distinctive pathophysiology, risk factor, phenotypic and socioeconomic characteristics.11–13 In addition, South Asia exhibits differences in health service use, health care costs and quality of care compared with high-income countries (HICs).14 Well-characterized prospective epidemiological cohorts help study the natural history of diseases and the evolution of care in the region. This can advance the knowledge and science of cardiometabolic diseases and provide the infrastructure for interdisciplinary and dynamic scientific explorations.15 The Center for cArdiometabolic Risk Reduction in South Asia (CARRS) is a population-based representative sociodemographically diverse cohort of 30 874 adults with prospective follow-up in three major cities in South Asia—Chennai and Delhi in India and Karachi in Pakistan.16