This article reports results from a study of contextual influences on participation among people involved in congregation-based community organizing. Data are drawn from 11,538 individual participants in 115 congregations taking part in one of five local organizing initiatives in different cities over a five-year period. Analyses used 3-level longitudinal models with binary indicators of participation/non-participation in group meetings each successive year as the criterion. Time-varying predictors at level-1 included prior participation in group meetings as a control, the types of group meetings that participants attended, the number of face-to-face meetings held between each participant and organizing staff of the local organizing initiatives, and a measure of the involvement of participants' affiliation networks. At level-2, demographic information was collected for a subset of participants (N = 461) and was included in a separate model. Neighborhood compositional characteristics were examined at level-3, including median income, economic heterogeneity, and residential stability. Study results found that characteristics of organizational settings (i.e., types of group meetings attended and frequency of face-to-face contact) predicted future participation in group meetings but that individual and neighborhood-level demographic characteristics were generally not predictive of future participation in community organizing activities.