Objectives. We used results generated from the first study of the National Institutes of Health Sentinel Network to understand health concerns and perceptions of research among underrepresented groups such as women, the elderly, racial/ethnic groups, and rural populations. Methods. Investigators at 5 Sentinel Network sites and 2 community-focused national organizations developed a common assessment tool used by community health workers to assess research perceptions, health concerns, and conditions. Results. Among 5979 individuals assessed, the top 5 health concerns were hypertension, diabetes, cancer, weight, and heart problems; hypertension was the most common self-reported condition. Levels of interest in research participation ranged from 70.1% among those in the "other" racial/ethnic category to 91.0% among African Americans. Overall, African Americans were more likely than members of other racial/ethnic groups to be interested in studies requiring blood samples (82.6%), genetic samples (76.9%), or medical records (77.2%); staying overnight in a hospital (70.5%); and use of medical equipment (75.4%). Conclusions. Top health concerns were consistent across geographic areas. African Americans reported more willingness to participate in research even if it required blood samples or genetic testing.