This book collects information about the most popular ethnomedicinal plants, which are common in Turkey and around the world. It presents the ethnopharmacological records, in vivo and in vitro studies, side effects, chemical compositions and clinical studies of these medicinal plants. Its special focus is on the novel drug targets for disease and their possible mechanisms of action. It covers botanical descriptions the status of the plants, and food or drug interactions including precautions and warnings about the plants and the available market products. It provides an explanation of recorded and known plant administration dosages. Also, the gap between the traditional practice and scientific/clinical evidences in the use of ethnomedicinal plant is acknowledged. It is well known that traditional knowledge of the use of the medicinal plants in therapy is an important resource for the discovery of novel treatment options and drug targets.