An etiological analysis of the inverse relationship between social class and mental impairment is presented. The empirical analysis failed to support the hypothesis that within a social class disadvantaged ethnic groups have higher rates of mental impairment than advantaged ethnic groups. In general there was no difference between the rates for advantaged and disadvantaged ethnic groups. Further, this finding was not altered when the conditions of social class, age, sex, marital status, and self-reported physical health were controlled. A secondary analysis is presented which indicates that normative strain as an objectively defined condition of the social system may not directly affect mental impairment rates. The theoretical and methodological implications of objectively vs. subjectively defined normative strain are discussed. It is suggested that future research explore the differential predictive power of both objectively and subjectively defined normative strain relative to rates of deviance. (Author)