Australian and New South Wales Sexually Transmissible Infections Strategies recommend sexual health clinics actively target particular populations, including men who have sex with men (MSM), who have increasing rates of sexually transmitted infections (STIs). We describe trends in MSM attendances, STI testing and diagnostic yield from 1996 to 2007 at a Sydney public sexual clinic. Aggregate data were extracted from the clinic database. There was a 76% increase in the number of individual MSM attending, more than three-fold increase in the number of STI tests performed and the proportion of MSM tested. The increase in testing was greatest for rectal infections. The positive yield increased for rectal chlamydia and infectious syphilis; remained stable for pharyngeal gonorrhoea; and decreased for urethral gonorrhoea, rectal gonorrhoea and urethral chlamydia. Our results demonstrate successful service reorientation in response to a local STI epidemic. Differing trends suggest evolving transmission dynamics for different STIs in the context of increased testing of asymptomatic MSM.