Casein is the name for a family of related phosphoprotein proteins. These proteins are commonly found in mammalian milk, making up 80% of the proteins in cow milk and between 60% and 65% of the proteins in human milk. Casein has a wide variety of uses, from being a major component of cheese, to use as a food additive, to a binder for safety matches. In this book, the authors present topical research in the study of the production, uses and health effects of casein, including the technological aspects of caseins of goat and sheep milk; the use of casein and casein-derived proteins as agents to inhibit dental erosion; the genetics of caseins in domestic ruminants; mineral carriers and potential nutraceuticals of casein phosphopeptides; caseins in traditional Portuguese cheeses; using casein protein for microspheres’ synthesis, encapsulation drug and textile coatings and the antimicrobial activities of casein and other milk proteins.