Antimicrobial Peptides, Volume 663 in the Methods in Enzymology series, highlights new advances in the field, with this new volume presenting interesting chapters on Unifying the classification of antimicrobial peptides in the Antimicrobial Peptide Database, Optimizing peptide library creation for PepSAVI-MS (RP libraries, etc.), Discovery of novel Antimicrobial peptides using BioProspecting, Screening for cysteine-stabilized scaffolds for developing protelytic-resistant AMPs, Exploring synergy and its role in antimicrobial peptide biology, Colorimetric assays for the rapid and high-throughput screening of antimicrobial peptide activity against diverse bacterial pathogens, and much more. Other chapters cover Liquid chromatography-mass spectrometry-based analysis of naturally occurring neuropeptide diastereomers, Multiplexed Quantitative Neuropeptidomics via DiLeu Isobaric Tagging, In vitro evaluation of antibiotic resistance via proteomics, Molecular networking-based strategies in mass spectrometry, Development of Macrocyclic antimicrobial peptides and peptoids, and a host of other timely topics.