Objective: Sex On Premises Venues (SOPVs), where men have sex with other men, provide an environment where the transmission of sexually transmitted infections (STIs) is potentially enhanced. However, the extent to which SOPVs contribute to STI transmission is unknown. This study aimed to obtain detailed data on the types of sexual practices and frequency of these practices among men who have sex with men (MSM) visiting SOPVs in Melbourne, Australia. Methods: In a cross-sectional study, MSM visiting 6 Melbourne SOPVs between December 2006 and February 2007 were asked to complete an exit survey on the types of sexual practices and frequency of such practices they had engaged in at that visit. Of 447 men approached, 150 (34%) participated in the study. Results: The median age of participants was 42.5 years (range 20-79). Among participants who engaged in receptive oral sex (66%) and insertive oral sex (75%), the median number of such acts reported by each man during the visit was 2 (range 1-10) and 2 (range 1-10) respectively. Eleven men (7%) reported receptive oral sex with ejaculation into their mouth with a median of 1 act (range 1-3) per man. Among participants who engaged in receptive anal sex (19%) and insertive anal sex (38%), the median number of such acts per man during the visit was 1 (range 1-4) and 1 (range 1-8) respectively. Eleven men (7%) reported unprotected insertive anal sex with a median of 1 act (range 1-4) per man; 4 (3%) reported unprotected receptive sex. A substantial number of men who did not report any anal sex engaged in practices potentially capable of transmitting infections. Notably, 44 men (29%) reported unprotected rubbing or touching of their penis ('nudging') onto another man's anus without actual anal penetration with a total of 71 other men (median 1 act per man, range 1-10). When specifically asked, 17 (39%) of these men reported that they had not engaged in 'anal sex'. In addition, 32 men (21%) reported being the recipients of 'nudging' with 40 other men. Fourteen (44%) of these men reported not having had any 'anal sex'. Oro-anal sex, whether 'active' or 'passive', was reported by 57 (38%) of men, while 84 (56%) men reported anal penetration using fingers, whether receptive or insertive. A significant minority (11%) of men reported that their ability to have safe sex was compromised by the use of drugs or alcohol. Of note, 58 (39%) men reported having a regular male partner, with whom 23 (40%) had unprotected anal sex. And 13 (9%) reported having a regular female partner, with whom 10 (77%) reportedly had unprotected vaginal or anal sex. Conclusions: The potential for STI transmission between men visiting Melbourne SOPVs and to their partners outside these venues is high. The contribution of what might be perceived as 'safer' sex practices to the transmission of STIs among MSM may have been underrecognised.