The Jackson Heart Study (JHS) is a single-site prospective epidemiologic investigation of cardiovascular disease (CVD) among African-Americans from the Jackson, Mississippi metropolitan area. It is a population-based longitudinal study representing an expansion of one of the study sites of the Atherosclerosis Risk in Communities Study (ARIC). The Jackson Heart Study was designed to build on the experience of the Jackson ARIC Cohort. Prior to the initiation of the Jackson Heart Study in 2000, a series of community meetings and focus groups were held and a survey was conducted to identify ways to enhance participation in the initial and subsequent examinations and strengthen awareness of CVD prevention. The Jackson Heart Study include 5,301 African- American men and women between the ages of 35 and 84, including 1,624 previous ARIC participants along with adults from a larger geographic area. Participants were randomly selected in order to be representative of African-American residents of Jackson, Mississippi. Family members were included in order to permit studies of familial and genetic contributions to CVD. The initial examination phase of the study began in the fall of 2000 and was completed in March 2004. An extensive examination included a series of questionnaires (examining lifestyle habits, medical history, medications, social and cultural factors), physical assessments (height, weight, body size, blood pressure, electrocardiogram, ultrasound measurements of the heart and arteries in the neck, and lung function) and laboratory measurements (cholesterol and other lipids, glucose, indicators related to clotting of the blood among others). The information collected in this study includes both conventional risk factors and new or emerging factors that may be related to CVD. Some of the newer areas of focus include early indicators of disease, genetics, sociocultural influences such as socioeconomic status and discrimination, and physiological relations between common disorders such as high blood pressure, obesity, and diabetes, and their influence on CVD. Exam 2 began in 2005 and ended in 2008, and Exam 3 began in 2009 and ended in 2012. Exam 4 is scheduled to begin in 2020 and end in 2022. The JHS, the largest investigation of CVD that has ever been undertaken in an African- American population, is sponsored by the National Heart, Lung, and Blood Institute (NHLBI) at the National Institutes of Health and was renewed in August 2018 for an additional six years. It is a partnership between NHLBI and four local institutions with six centers: Tougaloo College (Undergraduate Training and Education Center), Jackson State University (Graduate Training and Education Center), the University of Mississippi Medical Center (Coordinating Center, Field Center and Graduate Training and Education Center), and the Mississippi State Department of Health (Community Engagement Center). The NHLBI and JHS investigators from these institutions work closely together ...