The effects of membership and reference groups on attitudes toward women's employment were analyzed using four waves of the mature woman cohort of the National Longitudinal Survey. Attitudes, attitude change and change in employment and desire for employment were all considered. Evidence is presented for the influence of both membership and reference groups on attitudes and attitude change. Women who are employed and prefer to stay that way are more approving of women's employment at all points in time. In addition, employed women's rate of approval appears to be accelerating relative to the remainder of the sample;Attitude change toward increasing approval is divided into probability of adopting approval and the probability of maintaining that approval once it is adopted. The two rates are different and change differently over the period of the study. The probability of a woman maintaining approval of women's employment during the period from 1967 to 1972 is related to her own employment; women with some experience in the labor force are more likely to maintain approval than women outside the labor force. During the remainder of the study, however, the probability that women outside the labor force will maintain an approving attitude greatly increases relative to other women. It is suggested that the women's movement may have reinforced approving attitudes in women, regardless of their position in the labor force. Attitude change from disapproval to approval, on the other hand, is related to employment and this relationship remains constant throughout the study. Women in the labor force are more likely to change from disapproval to approval than are other women at all points in the study. Implications for the understanding of normative change are discussed.