Agricultural extension is evolving worldwide, and there is much emphasis today on community-based mechanisms of dissemination in order to bring sustainable change. The goal of this study was to examine the factors that make farmer groups successful in dissemination of information and technologies. A mixed-methods, multiple-stage approach was used to obtain data, using participant observation, documentary analysis, semi-structured interviews, social mapping, and structured questionnaires. Dairy-goat farmer groups (n = 46) and individual farmers (n = 88) were interviewed. Factors that were associated with group success in dissemination included member participation, degree of jealousy within the group, homogeneity of members, group capacity, number of linkages and type of group (project-supported versus non-supported). Some interventions that may increase the success of groups in dissemination include capacity-building, increasing linkages with other extension stakeholders, providing an enabling environment for groups to form, using established groups (as compared to forming new groups), and encouraging groups to form around common interests rather than for other reasons. (Contains 3 tables and 2 notes.)