‘Land’, a key production factor for the Dutch economy, was a topic extensively analysed by the founding fathers of modern economics, Adam Smith and David Ricardo. Until now, however, its precise value to the Netherlands’ economy has remained unclear (terra incognita). This study quantifies the direct economic value of the Dutch ‘land sector’. It also estimates the social benefits of sustainable land policy, providing an indication of the potential benefits of a policy geared as far as possible to sustainability. The study was commissioned to mark the 25th anniversary of Dutch soil protection policy and the Technical Committee on Soil Protection, TCB. The results were presented at the Terragenda congress held on 11 October 2012.