Prostitution has not received the academic interest it deserves in Poland. On the one hand the issue of eroticism and human sexuality is a relatively strong cultural taboo, on the other research on prostitution raises numerous methodological difficulties. The purpose of this article is to explore two issues. The first is go back to unsatisfactory attempts to define the commercial sex. The second is to look at legal regulations regarding this issue in Poland and several European countries. At the level of sociological reflection, prostitution can be defined by referring to the elements of a specific interaction between two people, one o whom offers paid sex and the other of whom is interested in using such a service. Prostitution is defined completely differently in law and in several European countries, for example in Great Britain and Austria there are interesting legal provisions. But I propose my own definition of prostitution or sex work in which the eight elements are combined. As far as legal regulations of prostitution are concern four categories of countries can be mentioned in Europe. From these in which the provision and purchase of sexual services is prohibited, to those where prostitution is legal and the professional status of the person engaging in it is regulated. There is also variety of perceptions of prostitution as a social phenomenon and different typologies of policies implemented by individual countries. But it appears that further studies on sex business and prostitution as a social phenomenon are needed.