This article represents a replication and extension of a previous study by Israel and her colleagues that investigated the relationship between psychological well-being and social network characteristics. The present research included both a comparable sample of white women (N = 104) between the ages of 60 and 68 (as in the original study), and a more extensive adult population of men and women (N = 718) between the ages of 50 and 95. The network characteristics examined are categorized along three broad dimensions: Structure--linkages in the overall network (size and density); interaction--nature of the linkages themselves (frequency, geographic dispersion, and reciprocity); and functions that networks provide (affective support and instrumental support). The results indicate a predominance of comparable findings for both the replication and extension studies. Of the eight network characteristics examined, the results of five of the regression analyses were the same across all three studies. The network characteristics of size, density, geographic dispersion, reciprocal instrumental support, and instrumental support did not make a significant contribution to the variance in psychological well-being. Of the other three network characteristics, the effect of frequency of interaction varied across the studies, and a pattern of significant results was found for affective support and reciprocal affective support. A discussion of this evidence in light of current literature and implications for practice and research is included.