Basic information on antibiotics and other biologically active prod-ucts are presented in these two easy-to-read volumes. The first volume is devoted entirely to antibiotics and consists of data as-sembled from the Index of Antibiotics from Actinomycetes. High-lighted are antibiotics from bacteria and from phycomycetes and other fungi. Mutasynthetic antibiotics are also discussed. In the second volume, data on biologically active substances is pre-sented. Antiviral compounds, pharmacologically active compounds from microbial sources and plant products not readily considered antibiotics are featured. In addition, compounds produced commer-cially by fermentation and some products of the "new biotechnol-ogy" are listed.