This international investigation was designed to determine if, and under what circumstances experiences at science centers, significantly correlated with a range of adult general public science and technology literacy measures. Given the complex and cumulative nature of science and technology learning, and the highly variable and free-choice nature of science center experiences, an epidemiological research approach was used. Quantitative surveys were administered to 6,089 adults living in 17 communities located in 13 countries; all with active science centers. Data collection and analysis protocols ensured a representative sampling based on age, education, and income from each of the 17 participating communities. Results showed that individuals who used science centers had significantly higher understanding, interest and curiosity, participation in free-choice leisure activities, and identity relative to science and technology than did individuals who did not visit; even when potential self-selection biases such as income, education level, and prior interest were taken into consideration. These findings significantly strengthen the argument that the presence of one or more healthy and active science centers within a community, region, or country represents a vital investment for fostering and maintaining a scientifically and technologically informed, engaged, and literate public.