The advent of the Data Web demonstrates how Web technologies can be employed to integrate dispersed, heterogeneous information. Most information – be it the product logistics status within supply chains, data warehouses of E-Commerce systems or offerings of the bakery shop next door – has a directly or indirectly associated spatial dimension. Integrating and efficiently using information with such a spatial dimension on the Web poses very particular challenges. First, we have to combine and reason about spatial and semantic features that use different vocabularies and representation techniques. Second, the wealth of pre-existing overlapping and complementary information sources in the spatial domain demands information management able to deal with billions of facts in a scalable manner. Third, only by dramatically lowering the entrance barriers extra value can be generated through the involvement of thousands of non-expert end users in authoring, curation and assessment. GeoKnow tackles these challenges and facilitates the transition from islands of isolated Geographic Information Systems (GIS) to a Web of interlinked Geographic Knowledge Systems (GKS). GeoKnow focuses on two complementary application scenarios: (1) spatial-semantic collaboration and data integration along value-chains in supplier and customers networks; and (2) spatial-semantic travel E-Commerce data management. GeoKnow will contribute to the evolution of the Web from a medium for information exchange to a medium for (spatial) knowledge integration. GeoKnow aims to help realizing network effects by increasing quality and coherence of the Spatial Data Web. For enterprises, the GeoKnow Generator will provide a cost-efficient way to integrate a variety of heterogeneous information sources within an Enterprise Data Intranet.