Teucrium species are an intersting object of research in the various aspects of science with multiple applications. With more than 300 species, Teucrium is one of the largest and well distributed genera of the Lamiaceae family. Known medicinal Teucrium species have a long traditional use as well as different potential applications in pharmacy, food and beverage industry. Teucrium species are very rich in a variety of secondary metabolites with significant biological activities. Based on that, the book contains 15 chapters which discusses recent advances in exploring the unique features of Teucriumspecies including morphology, systematics, taxonomy, biogeography, ethnobotany, phytochemistry, biological activity such as genotoxic, antioxidant, antibacterial, antifungal, antiviral, anticancer, anticholinesterase, antidiabetic and anti-inflammatory activity of secondary metabolites as well as applications including current challenges and further perspectives. Some medicinal Teucrium species in excessive use can cause certain consequences. This phenomenon and precaution is also described. Whilst this book is primarily aimed at scientists, researchers, beginners in the investigations of Teucrium species, graduate and post-graduate students in biology, botany, biotechnology, agriculture, and pharmacy, as well as science enthusiasts and practitioners involved in medicinal plants applications. Book provides complete Teucrium species list, color photographs of selected Teucrium species on natural habitats, as well as up-to-date bibliography related to Teucrium genus.