Plants continue to be the major source of drugs, inspite of the phenomenal development in the synthetic compounds during the last two decades. Due to the realization of the toxicity associated with synthetic drugs, the importance of plant drugs enhanced substantially in the recent years. This resulted in the increased demand of medicinal plants many fold. Since the availability of a number of important medicinal plants from natural sources was insufficient to meet the demands of pharmaceutical industries, large-scale cultivation of these plants came into existence. Commercial cultivation dramatically increased the disease problems, number of diseases and their severity, in these plants. No comprehensive compilation of the diseases of important medicinal plants and their control is available. This book Diseases of Major Medicinal Plants, is the first compilation of the available information of the diseases of important medicinal plants and their control.