This chapter discusses premalignancy of the cervix, as this is the most common of the preinvasive conditions and the only one that is screened for on a population basis. Several large randomised studies have now been completed and published and they have shown that quadravalent and bivalent types of vaccine effectively increase specific immunoglobulin G, reduce or eliminate infection with type specific virus and effectively eliminate preinvasive disease related to the vaccinated subtypes. Genital human papillomaviruses (HPVs) are divided into higher-risk types and lower risk types depending on their association with malignancy. If a woman has VIN, the rest of the lower genital tract should be carefully examined, as there is an increased risk of intraepithelial neoplasia at other sites. Local treatment for cervical intraepithelial neoplasia (CIN) is highly effective. Vaginal and vulval intraepithelial neoplasias are much less common and appear to have less invasive potential than CIN.