In order to describe trends in traffic accidents, mortality, vehicle types, fleet sizes, and victims' characteristics in Campinas, São Paulo State, Brazil, from 1995 to 2008, this study analyzed vehicle rates, traffic accident rates per inhabitant and per vehicle, case-fatality rates, proportional mortality, mortality rates, and rates ratios. The motorcycle fleet increased 241%. Although the case-fatality rate of motorcycle users from 2000 to 2008 decreased, in 2008 they accounted for 49.3% of fatal accidents on public byways in Campinas. Motorcycles were responsible for the highest run-over rate (66.7 pedestrians/1,000 accidents) and highest pedestrian fatality rate (4 deaths/1,000 accidents). Men showed much higher mortality rates than women. Pedestrian victims were mainly elderly; most vehicle occupants in traffic accidents were in the 15 to 29-year age bracket. From 2006 to 2008, nearly 80% of vehicle users 15 to 39 years of age were motorcyclists. Motorcycle accident prevention should be a priority, using multi-institutional measures.