Some aspects of the relationship of occupational gains of American Negroes during the 1940's to general changes in the occupational structure were investigated to throw light upon the hypothesis that the structural changes were necessary for the large Negro gains. If was found that Negroes made their greatest gains in rapidly expanding occupations, in occupations of intermediate and declining desirability, and in occupations much more desirable to Negroes than to whites. It was concluded that the large Negro gains would not have been possible without the great expansion in numbers of workers in the highly and moderately desirable occupations.