Background and objectives The incidence of ESRD is higher in African Americans than in whites, despite reports of a similar or lower prevalence of CKD. Design, setting, participants, & measurements This study compared the incidence of CKD among young African-American and white adults over 20 years of follow-up in the community-based Coronary Artery Risk Development in Young Adults study. Participants included 4119 adults, 18-30 years of age, with an estimated GFR (eGFR) ≥60 ml/min per 1.73 m 2 at baseline. Incident CKD was defined as an eGFR<60 ml/min per 1.73 m 2 and a ≥25% decline in eGFR at study visits conducted 10,15, and 20 years after baseline. Results At baseline, the mean age of African Americans and whites was 24 and 26 years, respectively (P<0.001), and 56% and 53% of participants, respectively, were women (P=0.06). There were 43 incident cases of CKD during follow-up, 29 (1.4%) among African Americans and 14 (0.7%) among whites (P=0.02). The age- and sex-adjusted hazard ratio (HR) for incident CKD comparing African Americans to whites was 2.56 (95% confidence interval [95% CI], 1.35-5.05). After further adjustment for body mass index, systolic BP, fasting plasma glucose, and HDL cholesterol, the HR was 2.51 (95% CI, 1.25-5.05). After multivariable adjustment including albuminuria at year 10, the HR for CKD at year 15 or 20 was 1.12 (95% CI, 0.52-2.41). Conclusions In this study, the 20-year CKD incidence was higher among African Americans than whites, a difference that is explained in part by albuminuria. © 2012 by the American Society of Nephrology.