An online GIS removes the need to collate elements in a single database, but appropriate standards and protocols are necessary. Online GIS & Spatial Metadata covers the principles, techniques and standards for online GIS, including online spatial information and data warehousing. The authors examine the idea of metadata and outlines why it is important. They explain the underlying methodologies, including relevant standards, and the tools and skills needed to manage metadata. Finally, the subject is placed in the context of global GIS: putting data online; creating metadata; creating virtual data warehouses; geographical agents, and spatial data mining.