The changing nature of families, their enduring and multi-faceted significance in society, and their value as a focus for the exploration of social change have ensured that families have remained a prominent focus of academic enquiry. Acknowledging the increasing diversity and complexity of families, this innovative book proposes a new conceptual framework for understanding families and other relationships that both challenges and attempts to reconcile traditional and contemporary approaches. Using the notion of 'boundaries', the book shifts thinking from 'families as entities' to 'families as relationship processes'. Emphasising the processes that underlie boundary construction and reconstruction suggests that the key to understanding family life is the process of relationship formation. The ideas of entity, boundary, margins and hybridity provide a framework for understanding the diverse, and often contradictory, ways in which families contribute to society. Three main themes are explored: the nature of families, families in society, and relationships and friendships. The three themes each include an exciting mix of contributions on different topics, from work and care, risk and social change to health, illness and well-being. Families in society makes a significant contribution to the academic literature on families and is essential reading for social science students, social researchers, policy makers and practitioners interested in families and relationships.