The aim of this book was to provide a comprehensive account of theories, methods, and technologies involved in GIS-MCDA procedures. This was achieved by: (i) explaining the fundamental concepts of MCDA and integrating those concepts into GIS-based methods, (ii) overviewing GIS-MCDA methods and demonstrating their applications in a wide variety of decision situations, and (iii) presenting a set of information technologies and decision support tools available for integrating GIS and MCDA methods. Specifically, the discussion of relevant concepts, methods, and technologies was organized into three parts: Preliminaries (Part I), Spatial MCDA: Methods (Part II), and Spatial MCDA: Technologies (Part III).Part I examined the linkages between GIScience, spatial analysis, and decision support (Chap. 1). It then provided an overview of generic elements of MCDA and the basic concepts of GIS-MCDA including: value scaling, criterion weighting and combination rules (Chap. 2). Part I also outlined the development of GIS-MCDA research and applications (Chap. 3). We emphasized the spatial aspects of GIS-MCDA by making a distinction between spatially implicit and explicit evaluation criteria, criterion weights, and decision alternatives. This distinction was central for identifying two groups of MCDA methods integrated into GIS: conventional (spatially implicit) and spatially explicit MCDA methods.Part II discussed GIS-MCDA models and procedures including: multiattribute methods (such as the weighted linear combination, ideal point methods, the analytic hierarchy/network process, and outranking methods), and multiobjective optimization methods (such as generating non-dominated solutions, distance-based, and interactive methods) (Chaps. 4 and 5, respectively). In addition to the conventional methods, we presented a selection of basic heuristics (such as site suitability and site location heuristics, and greedy algorithms) and meta-heuristics (such as genetic algorithms, simulation annealing, tabu search, and swarm intelligence methods) for tackling complex decision situations (Chap. 6). We emphasized the relevance and