New Approaches for Flavin Catalysis, Volume 620, a new volume in the Methods in Enzymology series, continues the legacy of this premier serial with quality chapters authored by leaders in the field. Topics covered in this update include Anaerobiosis and Methods for Reduction, Reduction Potentials, Anaerobic Stopped-Flow, No Glove-Box, Anaerobic Stopped-Flow, in a Glove-Box, Chemical Quenching, Oxygen Reactions, Double-mixing Stopped-Flow, Kinetic Isotope Effects and Viscosity Effects, Heavy Enzymes Synthetic Flavins & Linear Free Energy Relationships, Vibrational Spectroscopy, Stark Spectroscopy, EPR and Related Methods, Molecular Dynamics, Phylogenetic Relationships/Superfamilies, O2 and Superoxide Analogs, and more.