 Peterson took his Chilean team on a grueling tour of the United States in 1972.From 1973–1978, he coached Virtus Bologna in the Italian LBA, winning the 1974 "Coppa Italia" and, in 1976, the Italian League title.In 1978, he was hired as head coach of Olimpia Milano, where he won four Italian League titles (1982, 1985, 1986, 1987), two more Italian Cups (1986, 1987), a Korać Cup (1985), and one European Champions Cup (EuroLeague) title, which is the highest title in Europe for pro club basketball.