This book offers a comprehensive exploration of bio-polymeric materials, with a special focus on their interfacial properties. It covers the latest advancements in bio-polymer applications at interfaces, examining their chemical structures, biological foundations, modifications, and diverse applications. The discussion highlights these materials as potential replacements for fossil-based products, while also demonstrating their broader capabilities that extend beyond simple substitution of petrochemical materials. The focus is on understanding the interfacial science of these materials, particularly the key functional groups, physical phenomena, and interactions that occur in specific environments. The book features contributions from experts in the respective fields, making it a reference for scientists, academicians, practitioners, and students who are involved in the development and application of sustainable materials.