Open-space preservation is a planner's issue that is constantly debated, in particular on the success of the implemented instruments. We analysed the contribution of Dutch policies to open-space preservation by comparing actual land-use developments within different restrictive planning regimes. The Green Heart is the central open space within the ring of cities in the western part of the country. Protection of this area aimed at providing residents from the surrounding cities with opportunities for outdoor recreation at a short distance. The Buffer zones were designated in areas with a considerable urbanisation pressure and were intended to prevent specific cities from growing together into a solid urbanised belt, thus keeping separate cities recognisable as such in the landscape. In total, 10 Buffer zones have been designated, in size ranging from very small (3 hectares) to considerable (8700 hectares). Two relatively small zones are found in the heavily urbanised area near the city of Maastricht in the southern tip of the country. The others, in total claiming just over 20,000 hectares, are situated in the Randstad. The impact of these zones on urban development was first analysed in the related paper by Koomen, Dekkers and van Dijk (2008). In a subsequent paper we followed up on this analysis with other and more recent land-use data study the impact of changes in spatial planning and test the robustness of the results (Koomen and Dekkers, 2013). The relevant spatial data files are provided here as separate shapefiles that can be used in many GIS packages. The data uses the Dutch Rijksdriehoekstelsel_New (RD_New) projection system.