Food proteins have gained increasing value in recent times and have become an interesting issue for scientific research due to the rapidly expanding knowledge about physiologically active peptides. Bioactive peptides released during gastrointestinal digestion or food processing such as fermentation, curing and ageing, and enzymatic hydrolysis, play an important role in metabolic regulation and modulation, suggesting their potential use as functional food ingredients for health promotion and disease risk reduction. A substantial amount of evidence indicates that animal proteins and peptides may exert several diverse biological effects, above and beyond fulfilling basic nutritional requirements. Studies suggest that peptides from various livestock products possess bioactivities, including antihypertensive, antioxidant, anticancer, antimicrobial, antiappetizing, opioid, mineral binding, immunomodulatory, cytomodulatory, and cholesterol-lowering effects, highlighting their importance in human and animal health, and disease prevention and treatment. This book focuses on peptides identified in the meat, blood, fish, milk, dairy products, and egg and their functional aspects.