Delinquency in a Birth Cohort, published in 1972, was the first criminologi- cal birth cohort study in the United States. Nils Christie, in Unge norske lovorertredere, had done the first such study as his dissertation at the University of Oslo in 1960. Professor Thorsten Sellin was the inspiration for the U.S. study. He could read Norwegian, and I could a little because I studied at the University of Oslo in my graduate years. Our interest in pursuing...