This book constitutes the refereed proceedings of the 9th International Symposium on Web and Wirelsss Geographical Information Systems, W2GIS 2009, held in Maynooth, Ireland, in December 2009. The 12 revised full papers presented together with two invited talks were carefully reviewed and selected from numerous submissions. The papers span a wide area including but not limited from geospatial analysis and personalization and semantic geo-spatial web to W2GIS case studies and web and mobile applications and prototypes.