Radical SAM Enzymes, Volume 606, the latest release in the Methods in Enzymology series, highlights new advances in the field, with this new volume presenting interesting chapters on the Characterization of the glycyl radical enzyme choline trimethylamine-lyase and its radical S-adenosylmethionine activating enzyme, Diphathimide biosynthesis, Radical SAM glycyl radical activating enzymes, Radical SAM enzyme BioB in the biosynthesis of biotin, Biogenesis of the PQQ cofactor, Role of MoaAC in the biogenesis of the molybdenum cofactor, Biosynthesis of the nitrogenase cofactor, Bioinformatics of the radical SAM superfamily, The involvement of SAM radical enzymes in the biosynthesis of methanogenic coenzymes, methanopterin and coenzyme F420, and more.