Propolis is a natural product, collected by honeybees Apis mellifera, from various plant sources. Honeybees use it for the construction and repair of their hive as well as for defense purposes. Propolis has gained popularity in alternative medicine. It is extensively used as a popular remedy in foods and beverages. The purpose of this book is to present readers with an integrated view on molecular mechanisms of beneficial effects of propolis in acute and chronic humans. This book will provide current and comprehensive information on the protective effects of propolis on human health and treatment chronic human diseases.