Dispositional styles of relating to significant others-adult attachment-are linked to social relatedness across the life span. Prior work has concentrated on the receipt of perceived social support and not examined links between attachment and patterns of exchange. Data from a sample of older adults (N 1,118) were used to examine how secure, dismissive, and fearfully avoidant dimensions were associated with network size and patterns of exchange in kin and non-kin networks. Security was related to larger network size, greater reciprocity, and less "giving" to kin, whereas dismissiveness was associated with smaller non-kin networks, greater reciprocity, less "giving" to kin and non-kin, and more relationships involving "receiving" from kin. Levels of fearful avoidance were associated with fewer reciprocal relationships and more "receiving" from kin. Data are interpreted in light of attachment's manifestations in motivational and interpersonal systems and may help explain variations in later life social network functioning. © The Author(s) 2011.