This study investigates the influences on young women's sexual risk taking of (a) attitudes such as sexual self-efficacy and sexual self-esteem and (b) personal and sexual characteristics, such as age, the age of first sexual experience, the number of sexual partners and reported overall amount of sex. Three hundred and thirty-one young women participated in this study. With respect to regular sexual relationships, the results show that risk taking behaviour is directly and positively associated with sexual self-esteem. The effect of sexual self-efficacy on risk taking in regular relationships, however, is indirect and positive, being mediated by the overall amount of sexual activity. In contrast, with respect to casual sexual relationships, risk taking behaviour is negatively associated with self-esteem and positively associated with sexual self-efficacy. In addition, sexual self-esteem influences casual risk taking indirectly and positively, the effect being mediated by the overall amount of sexual activity. The findings in relation to sexual self-esteem and sexual self-efficacy are contrary to the expectations that these variables would be negatively associated with sexual risk taking behaviours. The implications for safe sex education are discussed.