The notion of social capital focuses attention on social connectedness within communities and the ways that this connectedness may affect health and well-being. There are many competing definitions of social capital but most suggest that it involves trust, social networks and reciprocity within communities, not necessarily geographically defined. The usefulness of social capital and related theories that help in understanding the function of nurses in rural communities are explored in this paper. Nurses and health service planners are becoming increasingly aware of the potential contribution of community nurses in rural and/or remote areas, as evidenced in the development of nurse practitioners. Through their interrelational role and status in rural communities, nurses are often 'immersed' or 'embedded' in the social networks that make up the fabric of rural life and may therefore be important contributors to social capital. For a concept such as social capital to be useful in nursing research, it must have distinct attributes, delineated boundaries, and well-described preconditions and outcomes in multiple contexts.