Synopsis There is no complete text in English on dravyaguna in accordance with CCIM syllabus. Earlier some attempts were made by H.V. Savnur and Moss in English. Still a comprehensive English text is in demand. With this background, the author has decided to prepare a unique text on fundamental concepts of dravyaguna as well as on drugs in English. This will be useful to the under graduate as well as the post-graduate students of Ayurveda. At the same time practitioners and teachers will also appreciate the references and subject matter. Karma chapter is discussed more elaborately with modern pharmacological actions. Several herbs screened for biological and pharmacological activities are mentioned with relevant references. Research works related to Rasa, Virya etc., are also quoted wherever relevant or necessary. The panchabhoutik aspects of Rasa, Guna, Virya etc., are discussed in respective chapters with scientific background. Overall, the text is meant for every one who is interested to learn about fundamental principles of dravyaguna in Ayurveda. One can not forget the dictuma good physician is a good pharmacologist too". It clearly indicates that a thorough knowledge in the science of drugs engenders excellent success in clinical practice to the physician.