The carcinogenicity of the 15 HPV types with carcinogenic potential varies greatly. We wish to clarify clinical utility of carcinogenic HPV DNA testing in women 21 and older by understanding the unique properties of individual HPV genotypes for viral persistence and progression. Specifically, we seek to understand the timing and determinants of viral clearance versus persistence and, given persistence, the risk of progression to CIN3/cancer (greater than or equal to CIN3) among women infected with each type of carcinogenic HPV genotype at the ages when cancer occurs. The relevant natural history data are lacking. There are no NCI or other cohorts in which these and other questions are being adequately addressed.