In response to the growing HIV epidemic in Africa in the 1990s, microbicide technologies emerged from discourses of empowerment and imaginings of the sexual lives and agency of African women. This draws on an anthropological enquiry which explored narratives from Tanzanian women who participated in a microbicide clinical trial. In the context of the HIV epidemic in Tanzania, women's lives were full of uncertainty and insecurity and their sexual lives were situated in a wider discourse of urban women's sexuality linked to morality and power. Their narratives revealed that women participated in the trial to seek knowledge as well as to 'try' the gel. In relation to their concerns about sexual health, the gel was experienced as cleansing as well as enhancing sexual desire and pleasure. The idea of empowerment imbued in the gel and transported to the women through the clinical trial was meaningful to the women, and this and ideas of sexual health and pleasure suggest future and hopeful possibilities for such HIV prevention technologies. However, if made widely available the potential for enhanced inequalities and further intensified surveillance of women's sexual lives must be considered.