This chapter examines the use of SAS, which is perhaps one of the most commonly used large scale statistical analysis systems in use. SAS consists of a suite of software programs developed by SAS Software to provide the ability to access, analyze, and report on high volumes of data across a variety of business applications. Dating back to the 1970s, its primary use is for decision making and business intelligence support. SAS is designed to access databases as well as flat, unformatted files. The software offers a large array of statistical functions; however, SAS tends to be programming oriented. To be effectively used, its features should be achieved with SAS programming language, and each procedure includes several statements. For example, compared to Excel, executing a graphic procedure in SAS is much more complex.