Medicinal plants; the worlds oldest known health care products, play dominant role in traditional health medicine. Simultaneously, plants are one of the driving forces that play a key role in the development and advancement of modern studies on biological activities. This volume contains 24 chapters contributed from 16 far and east countries namely Austria, China, Czech Republic, India, Iran, Japan, Kingdom of Saudi Arabia, Mauritius, Nigeria, Poland, Portugal, Serbia, Slovakia, Spain, Turkey and USA. The volume reflects at various pharmacological properties, their mechanism of action and medical preparations used in disease management like cancer, diabetes, rheumatic diseases, Alzheimers disease, hepatoprotective, dental caries, depression and anxiety cognitive disorder, erectile dysfunction and infertility, and other health promoting properties. The volume also contains comprehensive review of significant bioactive compounds like polysaccharides, polyphenols, phenylethanoids, glycosides, genistein, silybin etc. New findings from the study of saffron (Crocus sativus) indicate a decrease of insulin resistance and metabolic syndrome. The protective benefits from several dietary compounds have been demonstrated against cancer, oxidative stress, inflammation and cardiovascular disorders and the physiological relevance as well as the molecular mechanisms involved in these effects are also discussed. One of the article describes the application of natural products in order to protect crops, fruits and vegetables against contamination with phytopathogenic and saprophytic fungi. Medicinal herbs namely linden (Titlia cordata), peppermint (Mentha piperita), rosemary (Rosmarinus officinalis), sage (Salvia officinalis) and thyme (Thymus vulgaris) were investigated in terms of their health-promoting properties and related bioactive constituents. Significantly, the use of natural immunostimulants in fish culture is a promising new development. This volume is aimed for professionals of interdisciplinary health sciences, pharmaceutical sciences, pharmacognosy, agriculture, botany, medicine, therapeutics, traditional medicine, complementary and alternative medicine, food technology, herbalism, medical and public health sciences, policy-makers and marketing and economic strategies. It is addressed to undergraduate, postgraduate, teachers and researchers.