This study examines the short- and long-term impact of AmeriCorps participation on members' civic engagement, education, employment, and life skills. The analysis compares changes in the attitudes and behaviors of participants over time to those of individuals not enrolled in AmeriCorps, controlling for interest in national and community service, member and family demographics, and prior civic engagement. Results indicate that participation in AmeriCorps led to positive impacts on members, especially in the area of civic engagement, members' connection to community, knowledge about problems facing their community, and participation in community-based activities. AmeriCorps had some positive impacts on its members' employment-related outcomes. Few statistically significant impacts were found for measures of participants' attitude toward education or educational attainment, or for selected life skills measures. Within a subset of community service programs that incorporate a residential component for members, the study also uncovered a short-term negative impact of participation on members' appreciation for ethnic and cultural diversity, which disappeared over time. The implications of these findings for future research on national service are discussed. © 2009 by the Association for Public Policy Analysis and Management.