Genetic mapping has been a major task of classical genetics. Ascribing mutations to genes, and genes to chromosomes, has required the development of a large number of tools, both experimental and analytical, that lie at the core of genetical thinking. With the advent of alternative (and often simpler) molecular methods, some such tools have become obsolete, at least in practice. Others, however, survive. This chapter describes two methods for genetic mapping currently used in the gram-negative bacterium Salmonella enterica, a close of Escherichia coli that remains a model organism in both bacterial genetics and microbial pathogenesis.