We have attempted to organise this book in such a way that it will be useful to everyone interested in the world of plants particularly those increasing number of people who are concerned with medicinal plants. Many of this valuable and useful group of plants are threatened with extinction, because of over exploitation and habitat destruction. My endeavour here is to make people aware of the potential of medicinal plants from all angles so that these life saving plants can be protected from total destruction. There is a need to identify the natural plant wealth and commercially viable species in each agro-climatic Zones, promote industries to produce phyto-chomicals, standardize the agro-techniques for cultivation and production of these plants particularly in forests waste lands and orchards as an additional income generating activity and also strengthen the research and developmental activity for evolving new herbal products and their production technology. In this book more than 800 genera are discussed covering nearly 1257 species. Almost all commercially important medicinal plants cultivated in, different part of the world has found a place in this publication. An integrated and comprehensive account of all related aspects of the subject such an nomenclature, description, distribution, cultivation, processing, physical and chemical properties of large selection of plants have been incorporated. However, we would like to mention here that many of the plants are poisonous in the unprocessed from and self medication with wild plants is not all advisable. Some of the information furnished here are yet to be proved scientifically. For treating any ailments, the plant drug should be administered only with the prescription of a registered medical practitioner. We hope that the information furnished in this book will make it easier to identify the medicinal plants and make their growing more thorough and satisfying.