I FIRST BEGAN to study sex and marriage in 1982 when I received a grant from the National Endowment of the Humanities to investigate marriage, divorce, and child custody among Mexican Americans and anglos in California. My previous work had concerned mental disorders. I wanted to determine how much of the behavior we labeled "mental illness" was actually produced by how we treated the people we called mentally ill, by what opportunities they had or didn't have, and by the institutions we put them in. Over a period of seven years I studied matched samples of mental patients, mental hospital staff, and the general public in Germany and the United States. I concluded that the evidence overwhelmingly favored the view that the major mental disorders are universal and they had a biogenetic basis. On the other hand, social factors--like family supports, social class, and whether patients were in custodial institutions, and if so, for how long--were often more potent determinants of what eventually became of people--whether they could lead relatively normal lives or not--than their diagnosis, symptoms, and medical treatment. I published a book and a series of articles stating this, and, happily, worldwide research sponsored by the World Health Organization later supported my conclusions. I thus began that study by assuming that part of the behavior of the mentally ill could be viewed as socially constructed roles, and my findings supported that view--as well as indicating that some equally valid evidence supported a biomedical view.