Anal cancer is overrepresented among gay, bisexual and other men who have sex with men (MSM), particularly those living with HIV. Australia was the first country to introduce a publicly funded national HPV vaccination program in 2007. This program was expanded to include schoolboys aged 12-13 years in 2013; with a 2-year catch-up for boys aged up to 15 years. In 2018, the 9-valent vaccine (covering genotypes 6/11/16/18/31/33/45/52/58) replaced the 4-valent vaccine in the national program. The goal of the HYPER3 study is to determine the prevalence of anal, genital and oral HPV among 200 young gay and bisexual men aged 16-20 years who were eligible for the school-based 9-valent vaccination. Participants will be required to complete a questionnaire and provide samples for HPV testing. No follow-up visits will be required.