[full article and abstract in English] This study examines the mechanism of the protection of customers of property developers that was introduced into Polish legal system by the Property Development Act adopted on 16 September 2011. Those customers are the weaker party to a property development contract that should be protected by the State. The article presents the very concept of the Polish property development contract, its substance and legal forms as well as its practical aspects. This issue of the protection of customers of property developers is of a great importance not only in Poland but also in other European countries that have experienced a boom in the real estate market in the last decade. The article discusses also the iss...