Neighbors in retirement housing were surveyed to identify distinguishing characteristics and natural helping styles of interactants within a dynamic informal support system. Findings confirm a typology of three neighborhood exchange types: (1) high helpers, who exhibit a quasi-professional style of helping without reciprocation; (2) mutual helpers, who show an interdependent style of give and take; and (3) neighborhood isolates, whose social ties and help sources are primarily outside the neighborhood. Service models suggested by natural helping styles include volunteer programs and self-help group interventions.