This paper is a summary of an investigation into family relationships of 200 elderly patients admitted consecutively to the Mont Park Mental Hospital, Melbourne, in 1965–66. From the study, some data of statistical significance concerning social aspects of mental disorders of late life were obtained. Most of these data concerned senile dementia, which was the diagnostic group to which one-third of the patients was allotted. The survey was the basis for a thesis submitted to the Department of Psychiatry in the University of Melbourne for the degree of Doctor of Philosophy.