Abstract: The development of the protected areas system in Europe led to collaborations among the administrations of the national parks in different countries. This was imposed by extension of the natural units that need to be protected even beyond the borderline of a certain country. The frequency of this kind of situations grows as many border sectors are natural (rivers, lakes, mountains and so on). In these conditions, a new category of parks appeared – the cross-border national parks – which require more involvement and effort on behalf of the respective countries, with the purpose of a better administration of the common natural and cultural patrimony. Countries, such as France, Italy, Switzerland, Germany, Czech Republic, Poland, Ukraine cooperate (at the level of the administration and organization of the parks) in this respect. In Europe there are 10 cross-border national parks, most of them being situated within certain mountain units (the Alps, the Pyrenees, the Carpathians, the Hercynian Massifs of the Central Europe) and the general tendency is given by their growing number. Besides the advantages offered by the protection of the natural environment, the cooperating states realize a material benefit, due to the fact that the so-constituted national parks attract a significant number of tourists from Europe and other continents.