Azzam, T. (2013). Mapping data, geographic information systems. In T. Azzam & S. Ever- green (Eds.), Data visualization, part 2. New Directions for Evaluation, 140, 69–84. Mapping Data, Geographic Information Systems Tarek Azzam Abstract This chapter offers an introduction to geographic information systems (GIS) and provides examples of how this approach to data visualization can help evaluators better understand the context in which they are working, conduct a deeper analysis of the data, and communicate using maps to illustrate important findings and patterns. The chapter also discusses the limitations of this approach and offers suggestions for those interested in integrating GIS in their evaluation practice. © Wiley Periodicals, Inc., and the American Evaluation Association. G eographic information systems (GIS) is a method of linking quan- titative or qualitative data to geographic markers and locations (Chang, 2007; Renger, Cimetta, Pettrgrove, & Rogan, 2002). This ability allows evaluators to create maps that combine program information with geographic characteristics that surround them. So why is GIS a poten- tially important visualization approach? The best way to illustrate its rele- vance is through an example of a study that utilized GIS to map the locations of tobacco billboards in the St. Louis, MO, area. Luke, Esmundo, 69 8 NEW DIRECTIONS FOR EVALUATION, no. 140, Winter 2013 © Wiley Periodicals, Inc., and the American Evaluation Association. Published online in Wiley Online Library (wileyonlinelibrary.com) • DOI: 10.1002/ev.20074 Note: The figures presented in this chapter can be viewed in color by accessing www .NDEdataviz.com and selecting Chapter 7.