Book excerpt: This book and its companion, Volume II, concentrate on new procedures--especially those based on the new molecular methodology--developed within the past decade. This volume outlines the approaches, techniques, and procedures applied to cell and molecular biology studies of mycoplasmas. Volume II deals with the new genetic and immunological tools applied to the diagnosis of mycoplasma infections of humans, animals, plants, insects, and all cultures, with particular emphasis on the association of mycoplasmas with the activation of AIDS.Key Features* Cultivation and morphology* Genome characterization and genetics* Membrane characterization* Cell metabolism* Taxonomy and phylogeny* Pathogenicity