This book constitutes the refereed proceedings of the 6th International Conference on Geographic Information Science, GIScience 2010, held in Zurich, Switzerland, in September 2010. The 22 revised full papers presented were carefully reviewed and selected from 87 submissions. While traditional research topics such as spatio-temporal representations, spatial relations, interoperability, geographic databases, cartographic generalization, geographic visualization, navigation, spatial cognition, are alive and well in GIScience, research on how to handle massive and rapidly growing databases of dynamic space-time phenomena at fine-grained resolution for example, generated through sensor networks, has clearly emerged as a new and popular research frontier in the field.