As a result of the establishment of the U.S.-U.S.S.R. Joint Program in Cardiovascular Diseases in 1972, lipid research clinics were established in Moscow and Leningrad in 1974. The U.S.S.R. component of this collaborative research consisted of two Prevalence Studies and a Follow-up Study, all of which closely followed the U.S. Lipid Research Clinics Prevalence Study protocol.