The richness of floristic composition of North Eastern Region of India is known to all, where orchids are one of the major components of the vegetation with about 800 species; nearly 191 species of orchids are available in Assam, as far as orchid studies in Assam state are concerned, no comprehensive account of orchid flora is available. Although some interesting publications of Assam in general and Southern Assam in particular, dealing with enumerations of species, rare, threatened taxa and cultivation aspects are available. However several areas of Southern Assam (e.g. Barak Valley) still remain unexplored. The book is an effort to fill up this lacuna in study of our knowledge in the field of Orchids. The present work includes as many as 60 species belonging to 28 genera from the Southern Assam (Barak Valley). One new record from India, 5 new records from Assam and 1 rediscovered from the state. Species and genera described in this book are based on the fresh collections. Illustrations are also made from the type specimens by the authors. Synonyms of the taxa are given sufficiently in the text since many of the species are known in their different synonyms. Artificial key to genera has been provided. It is hope that, the book would be a helpful tool for the identification of orchids of this region not only for the taxonomists, but equally for the horticulturists, forest officials and other orchid lovers, and would thus help to update the status of the orchid flora (i.e. Orchid-diversity, rare, threatened and endangered orchids) in Barak Valley, thus helping in conserving this rich resource of Orchids. Contents: Foreword. Preface. 1. Introduction. 2. Taxonomic account. 3. Enumeration of orchid species. References. Taxonomical picture plates. Index.