Residential mobility changes lives and neighborhoods. Efforts to build strong communities are caught up with this dynamic but have insufficient understanding of its complexities. This study, of the Making Connections initiatives 10 target communities, evaluates push and pull factors of mobility decisions. Cluster analysis revealed discernible groups based on life cycle, economic factors, and neighborhood attachment. The study also investigated the effect of residential mobility on neighborhood composition, finding that change was primarily due to differences between movers and newcomersrather than changes for stayers. Study neighborhoods functioned in quite different ways that are relevant to well-being and community development.