Sugarcane breeding has until very recently been based solely on phenotype, and marker-assisted breeding of sugarcane remains in its infancy compared with that of row crops such as maize and soybean. A major reason for this is the complex genetics of sugarcane. This chapter reviews the uses of DNA marker technology in fingerprinting and diversity analysis of sugarcane. This is followed by a review of the development of linkage maps and initial trait/QTL mapping, including the Bru1 locus for resistance to brown rust (Puccinia melanocephala). Finally, the chapter reviews the use of newer next-generation sequencing–based technologies in sugarcane, including genome-wide association analysis and genomic selection.