This study attempts to test (via multiple regression analysis) hypothesized relationships between designated independent variables and age specific incidences of labor force participation for black male subpopulations in 54 Standard Metropolitan Statistical Areas. Leading independent variables tested include net migration, earnings, unemployment, education, percent inmates of institutions, and residential segregation. Other variables, believed less important theoretically or serving as controls, include percent black, percent in the armed forces, and industry mix (percent of employed black males in manufacturing). As anticipated, net migration, earnings, and unemployment emerge as leading determinants of labor force participation rates. But, in contrast to findings of past related research, there is scant evidence of expected positive education effects; this result underscores the problematic status of the "credentialism" or "demand for education" thesis. (CMG)