Australian guidelines recommend regular screening of men who have sex with men (MSM) for sexually transmitted infections (STIs). This audit was performed to determine STI testing rates in Sydney Sexual Health Centre before and after the development of the guidelines, and to describe characteristics of those not tested. The electronic clinic database and a manual file review were used to determine testing rates and reasons for not testing for the years 2000 and 2002. Overall testing rates were high, with 61% of MSM having had all recommended tests within the past year in 2002. There was a significant increase in testing rates for most tests after the development of the guidelines. Asymptomatic men were more likely to be tested than symptomatic men, and HIV-positive men were less likely to be tested for syphilis.