Coalitions currently are a popular tool for promoting community-based solutions to health problems, such as alcohol, tobacco, and other drug (ATOD) abuse. Private foundations, granting agencies, and other public health organizations assume that participation of community members in health promotion coalitions will increase the likelihood of program success. This article examines whether key characteristics of coalitions are related to effectiveness as measured by member satisfaction, commitment to the coalition, and the quality of planning efforts. Member survey data from the first year evaluation of an ATOD coalition were analyzed using factor analysis, chi-square, and multiple regression techniques at both the individual and group levels. The results suggest that community leadership, shared decision making, linkages with other organizations, and a positive organizational climate were key determinants of member satisfaction and participation. These same factors were not related to the quality of coalition plans. However, the significance of coalitions for community empowerment and health promotion is discussed.