The registered number of cases of early infectious syphilis and of (ano)genital gonorrhoea among the attendees of the outpatient clinic for sexually transmitted diseases of the Amsterdam municipal health service shows a strong increase for both diagnoses in the period 1990-2001, notably in the last few years. Nearly all of this increase is accounted for by homosexual men. Syphilis increased mostly among men aged 35 years and over, gonorrhoea mostly among younger men. The population of older men also showed a distinct increase since 1997 in HIV incidence.