In recent years, a renewed interest in obtaining biologically active compounds from natural sources has been observed. Contributing to this world-wide attention towards formulations based on natural products are their low or absent toxicity, their complete biodegradability, their availability from renewable sources, and, in most cases, their low-cost if compared with those of compounds obtained by total chemical synthesis. A further drive to the study of compounds obtainable from natural sources is the increasing consciousness that destruction or severe degradation of rain forests and other wild habitats, including seas and oceans, will unavoidably result in the loss of unexamined species and consequently of potentially useful compounds. Owing to this renewed attention to pharmaceuticals, agrochemicals and nutraceuticals (functional foods) obtained from natural sources, the study of bioactive secondary metabolites, traditionally carried out mainly by chemists, has increasingly attracted the attention of pharmacologists, biologists, botanists, agronomists, etc. stimulating co-operative work. This book reinforces the interdisciplinary approach to the study of bioactive natural products, suggesting new research projects to scientists already involved with bioactive natural products and possibly attracting further researchers to this field. The book includes chapters focused on general methods; main topics in the research field of bioactive natural products; surveys on natural compounds displaying important pharmacological activities; and marine metabolites. This work offers an overview of the modern methodology in the search for bioactive compounds from natural sources, and will be useful to advanced students and research scientists from various disciplinary sectors related to natural products. Tringali; Corrado University of Catania, Italy,