Biflavonoids comprise a group of the flavonoid family that possess a variety of structures and biological activities of high relevance, such as anticancer, antibacterial, antifungal, antiviral, anti-inflammatory, antinociceptive, antioxidant, vasodilator and anticlotting. The chemistry of biflavonoids is very important in many fields of research, especially because these compounds are structurally different bioactive molecules with potential for biomedical applications. This book highlights the structural biflavonoid variability, rearrangements and different stereochemistry through about 470 structures distributed in some species of Angiosperms, Gymnosperms, ferns and mosses.