Over the last few decades, social psychiatry has demonstrated correlations between mental illness and certain broad social categories. At the same time clinical, genetic and psychological studies have continued their traditional interest in the illness of the individual. The divergence of these two approaches has left relatively unmapped a large area which is of considerable psychiatric interest; despite much descriptive work, very little has been clearly established (outside genetics) concerning mental illness in the small, closely-integrated group, of which the prime example in our culture is the family. Out understanding of how personal and social factors jointly contribute to mental ill-health might well be furthered by studies in this field.