The opening thesis for this monograph was the assertion that horizontal relations may not disregard those rights and freedoms which the Constitution guarantees to their parties. The constitutional provisions in this field have a restrictive impact both upon norms of private law, which must have regard for constitutional norms relating to rights and freedoms of an individual, as well as decisions by private entities that should shape their mutual relations with due regard for those rights. Thus, constitutional rights set the limits for the freedom of contract, or, more generally speaking, the autonomy of will of private entities. Endowing constitutional rights with a horizontal, and thereby also a universal, dimension is a necessary condition for ensuring their real protection. In a contemporary democratic country, it is usually not the functioning of state authorities, but that of private entities that poses the greatest threat to constitutional rights and freedoms. Some of these entities exercise powers comparable to state powers, and thus have a state-like capacity to subjugate individuals. Doubts as to whether these entities and their functioning fall under the private law or the public law trigger further doubts as to the nature of legal relations they engage in. It is so, since these relations are less and less traditional horizontal relations between equal entities, and more and more vertical relations resembling those existing between an individualand the state.

The main purpose of my research was to answer the question of how and to what extent constitutional rights can apply in horizontal relations under the Polish Constitution. Determining the effect of these rights was preceded by analyzing constitutional provisions, judicature and jurisprudence in selected countries, where this problem has enjoyed enduring popularity for decades now. This analysis allowed distinguishing three models of the horizontal effect of constitutional rights. These models are neither mutually exclusive nor do they compete with one another, hence their concordant application is possible and even desirable. Each of these models views the effect of constitutional rights in horizontal relations from a different perspective, and all of them pursue the same goal, namely guaranteeing an effective protection to an individual at all possible planes of his activity.