We have performed a serological survey of HPV type 16-antibody prevalence by age and sex in Sweden and used it as a basis for modelling the optimal vaccination strategies in this population. Samples of 3,317 subjects were tested for HPV16-specific antibodies. The observed age-specific seroprevalences along with sexual behaviour data were used to infer parameter values for a mathematical model representing Sweden and the preventive effect of possible strategies estimated. By the year 2055, vaccination of females starting at age 12 in 2008 was most efficient, estimated to prevent 5.8 million cumulative HPV16 infections. Catch-up programs had a strong additional preventive effect. Vaccination also targeting males increased protective effect by about 4%, but had lower preventive effect per vaccination given. Addition of an HPV serosurvey to existing models and data has enabled us to estimate effect of different vaccination strategies, optimized to the HPV epidemiology in our population.