The present compendium is first of its kind providing valuable data on 917 species belonging to 571 genera and 133 families of root drug plants of ethnic India; covering details of nomenclature, English, Hindi and Sanskrit names, Distribution, Part (s) used, Utilisation, Active constituents, Biological activity and the original source of Information. Over thirty-six photographs, three histograms, three tables and eight appendices enhance the value of the compilation significantly. It is hoped, this invaluable compendium with its comprehensive coverage of the subject would help researchers and the medicinal plant industry in general for development of newer plant based drugs for alleviating human suffering. Audience: Students and Scholars of Ethnobotany, Economic Botany, Pharmacists, Medical Practitioners, Chemists, Biotechnologists, Plant Genetic Research Institutions, Policy Planners.