Adults with intellectual and developmental disabilities have medical conditions similar to those among the general population but with more complex presentation, a extended life expectancy, and increased risk of morbidity and mortality. These adults' health education has been inadequate. In this qualitative study, the author describes the experiences of 23 registered nurses who provide health teaching to adults with intellectual and developmental disabilities, selection of and health topics taught, and teaching activities put into practice. The author used a rigorous descriptive, naturalistic inquiry design with purposive (n = 22) and snowball (n = 1) sampling. Data were gathered through individual interviews, focus groups, and nonparticipant observations, and analyzed with a constant comparative method. Findings concerned the educators' developmental process, use of a social context to teach, and health-teaching activities. Registered nursess described their transformation from insecure, novice health educators to confident and passionate educators of adults with intellectual and developmental disabilities. Findings apply to multiple disciplines.