Book excerpt: Following the successful and proven concept used in "Bioactive Heterocyclic Compound Classes" by the same editors, this book is the first to present approved pharmaceutical and agrochemical compounds classified by their carboxylic acid functionality in one handy volume. Each of the around 40 chapters describes one or two typical syntheses of a specific compound class and provides concise information on the history of development, mode of action, biological activity and field of application, as well as structure-activity relationships. In addition, similarities and differences between pharmaceuticals and agrochemicals are discussed in the introduction. Written by a team of experts in the field, this is a useful reference for researchers in academia and chemical or pharmaceutical companies working in the field of total synthesis and natural product chemistry, drug development, and crop protection research.