This paper will analyze the quality of spatial planning in the Dutch conurbation Randstad Holland. Due to its strong economic development and its large role in the Dutch economy, this conurbation attracts a large number of residents and companies, which are the reason of great demographic and environmental pressures on the area, which are spreading to the "Green Heart" (low. Groene Hart), an agricultural zone at the center of the conurbation that has great importance for the Dutch agriculture, but also for the world agriculture. The aim of this paper is to explain which projects in spatial planning of this conurbation are implemented, who participates in them, how is the cooperation between those who participate in these projects and which results have brought the same. For this purpose, the development of conurbation will be compared with the development of other parts of the Netherlands, and attempts will be made to find opportunities to spatial relieve of Randstad Holland and encourage the balanced development of all parts of the Netherlands. Furthermore, the economic development of the Randstad Holland conurbation will be compared with the economic development of other large urban regions in northwestern Europe (London, Paris and Rhein-Ruhr) to further explain the development as well as Randstad’s role in the wider area. After that, the attitudes of other authors on spatial planning in Randstad and Green Heart will be analyzed in order to easier determine the guidelines for sustainable economic development of the conurbation area, which will be defined in the conclusion.