This is the thoroughly revised and updated edition of the popular textbook, prepared and designed to suite the requirements of the latest syllabus for first year Diploma in Pharmacy course prescribed by Pharmacy Council of India (Course Code ER20-13T). It lays emphasis on providing a consistent and readable format for a clear understanding of the concise description of various aspects of the science of crude drugs. The traditional herbal drugs are discussed to provide a link among current findings. It discusses the biological sources, chemical constituents and therapeutic efficacies of crude drugs, basic principles involved in the traditional systems of medicine, Ayurvedic formulations, health, food, herbal formulations, herbal cosmetics and phytochemical investigation of drugs. The arrangement of the subject matter is based on the pharmacological activities of the herbal drugs. Biological sources, distribution, cultivation, chemical constituents, and therapeutic uses of the herbal drugs are discussed throughout the book. Separate chapters on the classification of drugs, quality control of crude drugs, isolation, identification tests, therapeutic activities and pharmaceutical applications of herbal drug constituents are included to develop students' familiarity. Following the abovementioned properties, figures of the crude drugs and structural formulae of important chemical constituents of each herbal drug are discussed.