This chapter looks at the concepts and theories underlying the application of GIS in business. It discusses the role of information technology in business generally and how GIS is related to other business systems. Different views of GIS use are introduced and the chapter suggests that decision support applications of GIS are more relevant to most businesses than purely operational applications. Porter’s value chain approach is used to assess the potential of GIS to contribute to management. GIS is seen as an emerging technology that will increase importance in business in the future.