This paper evaluates the effectiveness of a bar-based, peer-led community-level intervention to promote sexual health amongst gay men. The intervention consisted of peer education within bars, gay specific genitourinary medicine (GUM) services and a free-phone hotline. Data were collected at baseline (1996) and at follow-up (1999) in gay bars in Glasgow (intervention city) and Edinburgh (control city). During the intervention peer educators interacted with 1484 men and new clients increased at the gay specific GUM service. However, the hotline was under-utilized and abused. The outcome measures were: reported hepatitis B vaccination; HIV testing; unprotected anal intercourse (UAI) with casual partners; negotiated safety; and amongst men reporting UAI with a regular partner, the proportion who knew their own and their partner's HIV status. Significant differences in sexual health behaviours were observed across locations and across time, but the only significant intervention effects were amongst men who had direct contact with the intervention, with higher uptake of hepatitis B vaccination and HIV testing. The intervention did not produce community-wide changes in sexual health behaviours. These results question the replication and transferability of peer-led, community-level sexual health promotion for gay men outwith the USA and across time.