This document explores the field of social network theory (with particular emphasis given to Australian research literature) by identifying and evaluating the major explanatory models in use--which have origins in such diverse disciplines as anthropology, sociology, social psychology, and social psychiatry--and by summarizing important findings; it also presents a theoretical critique of the social network perspective as applied to the study of social support. The chapters in part 1 deal with: (1) the reasons behind the growth of the social network perspective; (2) the effects of particular kinds of network structure on personal wellbeing; (3) the effects of such social factors as income and values on social network structure; and (4) the available literature on service delivery through "natural networks" and "network therapy." Part 2 deals with the methodological issues involved in research on support networks. It provides a discussion of the problems involved in collecting and analyzing support network data and a review of solutions that have been proposed to deal with these problems. The document contains an appendix, in a checklist format, which classifies social network literature according to the kinds of empirical, theoretical, or methodological information it contains. (WAS)