The author reviews the historical background of interparental child custody disputes. The father's superior right to custody in the nineteenth century continued the English common law tradition, but in the twentieth century the mother's claim became superior to the father's, reflecting women's generally increasing rights and the assumption that women are better suited to caring for children. Partly as a result of recent cultural changes leading to a beginning equalization of parental rights and partly because of greater concern for children, courts are starting to focus more on children's emotional needs. It is likely that courts will increasingly call on psychiatrists and other mental health professionals for help in making their decisions.