The American philosophy of social mobility has traditionally focused upon equal opportunity to succeed rather than the actual equality of socioeconomic status from the outset. Two replicate studies of social mobility in the U.S. undertaken in the early sixties and seventies enable social scientists to measure shifts in opportunities for American men. General findings about recent trends are presented in this document. Typically, American children have acquired more schooling than their parents, and access to a high school education has increased for the less advantaged. This greater equality of precollege education by social trends, however, tends to mask the persistence of unequal opportunity for a college education. In terms of job opportunities, occupational mobility of whites did not change between 1962 and 1973, but that of blacks did. In 1962, there was little relationship between the occupational position of the black man and that of his father. In 1973, there was evidence that the occupational positions tended to persist across generations for both blacks and whites (although there is also substantial occupational mobility). In terms of income opportunities, the relative economic returns of college education have declined for young whites but not for young blacks. This latter phenomenon has contributed to a relative "catching up" of the black minority. (Author/GC)