Research projects in the past year have focused on evaluating incidence trends for HPV-related and HPV-unrelated head and neck cancer sites internationally;investigating historical trends in the proportion of oropharynx cancers attributable to HPV infection in the US;and characterizing the proportion of oropharynx cancers attributable to HPV infection in India, a region with very high incidence of head and neck cancers. Research strategies included both population-based registry analyses and molecular epidemiologic analyses of tumor tissues.