Since the first edition of the Open Source GIS: A GRASS GIS Approach was published in 2002, GRASS has undergone major improvements. This second edition includes updates to many associated with new development; text is based on GRASS version 5.3 from December 2003. Open Source GIS: A GRASS GIS Approach, Second Edition, provides updated information about the use of GRASS, including geospatial modeling with raster data, vector and sites, image processing, visualization, and coupling with open source tools for geostatistical analysis and web applications. Open Source GIS: A GRASS GIS Approach, Second Edition is designed for the professional audience, composed of researchers and practitioners in government and industry.