The aim of this study is to analyse the effects on sex workers of new regulations that ban the practice of street prostitution in Spain. This country has not traditionally maintained a clear policy regarding prostitution. However, in recent years there has been a clear turn towards the criminalization of behaviours related to voluntary prostitution. The city councils of several Spanish cities have banned the practice of street prostitution and sanctioned it with fines issued to both prostitutes and clients. Even if few studies on prostitution have been carried out in Spain, none of them had yet analysed the effects of the adoption of civic ordinances on sex workers. In this paper we present the results of an empirical research carried out with a sample of 79 sex workers e in 20 cases with in-depth interviews e to explore the effects of the new regulation on their labour conditions.