The 1991 National Survey of Women (NSW) was conducted as a follow-up to the 1983 Survey of Unmarried Women (NSU), which examined sexual, contraceptive, and fertility behaviors, and the factors associated with these behaviors in a nationally representative probability sample of 1,314 never-married women between the ages of 20 to 29. The NSW sample consists of two subsamples of women. Women in the first sub-sample (n=929) were first interview ed as part of the NSU in 1983 when they were 20-29 years old and had never been married. These women were subsequently traced an reinterviewed in 1991. The second subsample of women (n=740) was obtained from a new area probability sample of 20-27 year old women, regardless of marital status women in this latter sample were interviewed for the first time in 1991. The combined sample consists of 1,669 women who were 20-37 years old in 1991. In-person interviews were conducted using a standard questionnaire and assessed information regarding respondents' personal back-ground; pregnancy history; sexual initiation and current exposure; current husband or partner; previous marital relationships; non-marital sexual partners; nonsexual romantic partners; health and risk-taking behavior; attitudes, perceptions and knowledge regarding health and contraception; and condom use. A self-administered questionnaire, which assessed self-esteem, locus of control, and attitudes toward marriage, was also completed by respondents. The NSW includes a total of 1,669 cases and 2,236 variables.