The relative benefits and hazards of noncontraceptive hormone therapy (HT) for aging women remain a controversial medical and social issue. This study examined the lifetime incidence of HT use, how usage varied by surgery status, and the bivariate and net associations between a large array of SES indicators and the likelihood of midlife women ever using HT by age 53-54 among N=3,612 non-Hispanic white women participants in the Wisconsin Longitudinal Study . About half the sample of women had ever used HT; 79% who had ever used HT were currently using HT (38.5%). In multivariate logistic regression analyses, the most robust SES predictor of HT use was a woman's husband's occupational status (higher status associated with higher rates of use). This association withstood adjusting for all other measured sociological and biomedical factors (e.g., other health behaviors, menopausal symptoms, age at menopause, health insurance). The association of HT use and education differed for women who underwent hysterectomy and/or oophorectomy (where the odds of using HT were higher for less educated women) and for women with intact reproductive organs (where the odds of using HT were lower for less educated women). Only among women who had surgery was the association of education with use of HT persistent adjusting for all other measured factors. Additionally, a woman's own earnings and household net worth showed positive net associations with HT use. Two competing explanations for the observed relationship between husband's occupational status and women's HT use are discussed: HT as a preventive health behavior and HT as a socially influenced behavior to help maximize femininity. Prevalence estimates of HT use have ranged widely depending upon the sampling frame of the study (Derby et al. 1993; Johannes et al. 1994;Thompson 1995). Rates of prescribing HT in the U.S. have been found to be highest in the West and lowest in the East (Hemminki et al. 1988). The use of HT is not random. While the most significant sociodemographic correlate of HT use other than age and gender is socioeconomic status (SES), SES has not been examined systematically in most studies of HT. SES is generally found to be positively associated with health-promoting behaviors and good health outcomes for both women and men (Adler et al. 1993;House et al. 1990House et al. , 1994Feinstein 1993; Longino, Warheit, and Green 1989; Marmot, Kogevinas, and Elston 1987;Syme and Berkman 1976;Waldron 1991). Yet considerable public health debate continues regarding the mechanisms and processes whereby SES influences differences in health behaviors and health status (Adler et al. 1993;Andersen 1995; Link and Phelan 1995). SES is measured in different ways -e.g., years of education, occupational status, and income. Different measures of SES tend to be only moderately correlated, and each captures different attributes of social status. One research approach to help elucidate the possible processes underlying any given relationship between a health outcome and S...