Given its wide use in education, business, and governmental agencies, ArcGIS is chosen as the major software platform to implement GIS tasks in this book. Unless pointed out otherwise, all studies in this book are based on ArcGIS 9.0. All chapters are structured similarly, beginning with conceptual discussions to lay out the foundation for methods, followed by case studies to get readers acquainted with techniques. Section 1.1 offers a quick tour of spatial and attribute data management in ArcGIS. Section 1.2 illustrates the typical process of GIS-based mapping in case study 1A: mapping the population density pattern in Cuyahoga County, Ohio. Section 1.3 surveys basic spatial analysis tools in ArcGIS, including queries, spatial joins, and map overlays. Section 1.4 illustrates some of the spatial analysis tools in case study 1B: extracting census tracts in Cleveland and deriving a polygon adjacency matrix. The polygon adjacency matrix deﬁnes spatial weights often needed in advanced spatial statistical studies such as spatial cluster and regression analyses (see Chapter 9). The chapter is concluded with a brief summary in Section 1.5.