Objectives To explore sex workers' accounts of condom use and their recommendations about how condoms might be improved.

Methods In-depth interviews were conducted with 22 female sex workers in sex work premises in London, UK and Amsterdam, The Netherlands.

Results The consistent and effective use of condoms was dependent upon client selection, sex worker control of the condom, communication skills and on condom- and sex-related skills. The design of facilities, the way the encounter was structured and alarm call systems were key to generating an environment in which sex worker control of the interaction was feasible. A wide range of practices used for 'safer sex', including the use of simulated vaginal sex, skills in fitting the condom in a sexually arousing way, checking the condom placement during intercourse and holding onto the condom during withdrawal, were described but awareness of such practices was piecemeal. Several sex workers said that particular care is needed when using condoms in men with a small penis and pointed out to the authors that a smaller condom would be useful.

Conclusions The sex workers told us about the importance of environmental factors and a range of sex- and condom-related skills in ‘safer sex’. Environmental ‘safety’ features could be addressed through a licensing system for sex work premises. Communication, condom- and sex-related skills should be more broadly disseminated through health promotion initiatives with sex workers. The issue of condom fit deserves further attention.