We aimed to determine whether the success of partner notification for gonorrhoea in men was affected by sexual orientation. Analysis of standard clinic and health adviser records of all male patients found to be infected with gonorrhoea between October 1992 and September 1993 were carried out. Of the 278 cases of gonorrhoea in men, 9% (25) were acquired through homosexual intercourse and 91% (253) by heterosexual contact. Fifteen per cent (24) of Caucasians were homosexual but only 0.9% (1) of Afro-Caribbeans were. The mean number of contacts was 1.36 for homosexuals and 1.38 for heterosexuals. Contact information was given by 55% of heterosexuals and 48% of homosexuals. The proportion of acknowledged contacts attending was 38% for homosexuals and 56% for heterosexuals (P = 0.054). Fifty-two per cent of homosexuals and 59% of heterosexuals had at least one contact attend. Data analysis on Caucasians only showed Caucasian gay men had a higher mean number of contacts (1.38) than Caucasian heterosexuals (1.28). Caucasian homosexuals had a lower proportion of contacts attending (40% vs. 77%) (P = 0.05), 54% of homosexual men and 60% of heterosexual men had at least one contact attending (P = 0.74). There is a trend for partner notification to be less successful in homosexual men when all ethnic groups are considered together. In Caucasian men with gonorrhoea, homosexuals have a greater number of partners than heterosexuals and have a lower proportion of total contacts attending but there is no difference in the proportion having at least one contact attending. Data on sexual orientation and ethnicity should be reported in studies assessing efficacy of contact tracing.