Spatial multicriteria evaluation (spatial MCE) is based on an integration of theories, methodologies, and software from geographic information systems (GIS) and multicriteria decision analysis (MCDA). Spatial MCE, also known as GIS-MCA or GIS-MCE (multicriteria analysis or evaluation), is well suited to semistructured problems. These problems often require several individuals (e.g., politicians, citizens) to choose from a set of alternatives (e.g., sites, strategies) despite uncertainties regarding how possible solutions should be generated or evaluated. Spatial MCE approaches augment GIS strengths in data management, spatial analysis, and map-based visualization with MCDA techniques that incorporate user judgment into evaluation processes.