Effective use of today's powerful GIS technology requires anunderstanding of the science of problem-solving that underpins it.Since the first edition published over a decade ago, this book hasled the way, with its focus on the scientific principles thatsupport GIS usage. It has also provided thorough, upto- datecoverage of GIS procedures, techniques and public policyapplications. This unique combination of science, technology andpractical problem solving has made this book a best-seller across abroad spectrum of disciplines. This fully updated 4th editioncontinues to deliver on these strengths.