Traditional folk medicine practices in China, Hong Kong, Japan and Korea - all located in Northeast Asia - are comparable. Since different usage of a folk medicine may reflect cultural or regional differences, a detailed collation of the folk knowledge of traditional medicine can help to identiy common applications derived from different empirical knowledge as well as variations in appreciation of the value of the same source in different cultural settings. The fourth volume of this book series continues with the objective of collating relevant information for showing the differences and similarities of traditional folk medicine practices around the world. It features 147 of the most frequently used medicinal plants, 43 animals, and 10 minerals in Northeast Asia as selected by the international editorial board. The folk medical knowledge in each entry includes the scientific names of the source, local names of the drug, special processing methods, administration methods, and applications in each country. Contraindications and side effects, if any, are highlighted. Relevant scientific data on their chemistry and pharmacology, with references, are also included. All this scientific information should be a valuable asset to medical and research scientists working on the bioactive components of natural products.