Abstract This article originates from an online ethnography on barebacking (intentional unprotected anal sex) in Brazil, between the years 2004 and 2008. More specifically, some elements or conceptual dimensions present in discussions on barebacking will be examined. Based on internet discussion forums and 23 open online interviews, using the Windows Live Messenger program, it was possible to organise the practice of barebacking into two principal modalities: more extensive and involving greater contact and partial or involving reduced risks. The individuals who practise bareback sex may experience situations that include various forms of barebacking during their lives, such as the men who contract HIV and try to develop strategies to reduce the risks in their sexual interactions by, for example, avoiding ejaculating inside their partner or trying to establish sexual relationships with men of the same serological status. Therefore, in general, the different motivations for barebacking constitute a frontier region (of tension) between the pleasure of sensory contact and the risk of infection. Beyond producing a dichotomy between pleasure and risk, the various meanings described by the potential barebackers must be taken into account.