Book excerpt: Analytical Microbiology focuses on the processes, methodologies, developments, and approaches involved in analytical microbiology, including microbiological, antibiotic, and amino acid assays and dilution methods. The selection first offers information on the theory of antibiotic inhibition zones, microbiological assay using large plate methods, and dilution methods of antibiotic assays. Discussions focus on serial dilution assay, requirements for accurate assay, microbiological assay of riboflavin, laws of adsorption and partition, mechanisms of antibiotic action, and biological considerations affecting the use of statistical methods. The text then ponders on the elements of photometric assaying and automation of microbiological assays. The manuscript elaborates on antibiotic substances, vitamins, and amino acids. Topics include assay organisms, validity, specificity, reliability, and calculation of results of amino acid assays, bacitracin, chloramphenicol, dihydrostreptomycin, erythromycin, neomycin, and streptomycin. The selection is a dependable reference for researchers interested in analytical microbiology.