While the stigma surrounding sex work is both well documented and easily recognised, few studies examine stigma in this context from the perspective of the sex workers themselves. In this article we report on a study using a modified grounded theory approach to analyse a series of semi-structured interviews with 49 female sex workers in Hong Kong, in order to examine the ways in which this group experiences and negotiates the stigma which arises from their employment in the sex industry. Sex workers in Hong Kong were subject to various stigmatising forces in their daily lives in their interactions with the public, the police and their families. These processes could have a negative impact on the sex workers' health, both through obvious manifestations such as physical or verbal abuse and through more subtle processes such as those which generated or perpetuated vulnerability and those which compelled the sex workers to conceal their identities and withdraw themselves from social networks. These findings are situated in the context of broader research surrounding sex work, drawing attention to the consequences of stigma on health and their interaction with health-service providers, before briefly discussing possible means of overcoming stigma-related barriers to providing adequate healthcare for this marginalised group.