Nucleotide sequence-based methods focusing on the single nucleotide polymorphisms (SNPs) of Listeria monocytogenes housekeeping genes facilitate the rapid and interlaboratory comparison on open accessible databases, such as the multilocus sequence typing (MLST) databases that are available. MLST has advantages over other methods as it can reconstruct ancestral and evolutionary linkage between L. monocytogenes isolates. MLST detects all genetic variations within the amplified housekeeping gene that accumulate slowly. This chapter describes how to undertake MLST.