Anthocyanins are a group of plant phenolics characterized by their blue-orange-red color. They have a double interest as plant constituents. A technological interest, since they can not only be used as natural colorants in the food industry but also can interact with other plant components influencing the final characteristics of the processed product. Anthocyanins show also interest related to their implications on human health, as they can be considered functional ingredients and have shown themselves as potential targets for the pharmacological industry. This chapter summarizes the existing literature in this area: From anthocyanin occurrence and phytochemistry to their biosynthesis, biological activities, and an overview of the biotechnological approaches that are in use at present.