The need for statistical analysis in single-subject designs presents a challenge, as analytical methods that are applied to group comparison studies are often not appropriate in single-subject research. "SSD for R" is a robust set of statistical functions with wide applicability to single-subject research. It is a comprehensive package of statistical tests and produces accompanying graphs for almost every function. These include, among others, tests of autocorrelation, t-tests, effect sizes, median and celeration chi[superscript 2] analyses, and control charts. All functions and graphs are described in a series of tables. Since "SSD for R" is open source, it is freely available and can be accessed on the authors' website, www.ssdanalysis.com. Additional support, including video tutorials and sample data are also available at no charge. (Contains 7 figures and 4 tables.)