Synthetic polymers are an important class of pharmaceutical excipients that contribute significantly to the fabrication of different dosage forms. However, due to biodegradability concerns, the highly publicized disposal problem of traditional oilbased thermoplastics with a detrimental effect on the environment, has promoted the search for alternative biodegradable polymers. Biodegradable polymers are an ecofriendly, economic, and safe alternative to synthetic polymers due to their biodegradable nature and the source of origin. Biopolymers and biomaterials are available in abundance with different pharmaceutical and medical applications including drug delivery, wound healing, tissue engineering, imaging agents, etc. Moreover, biopolymers possess certain specific properties such as biocompatibility, biodegradability, low antigenicity, functionality to support cell growth, and proliferation with appropriate mechanical strength. Biopolymers are obtained from sustainable natural resources and animal processing co-products and wastes. Polysaccharides such as cellulose and starch represent the major characteristics of the family of these natural biopolymers, while other biodegradable polymers such as bacterial cellulose and sericin are also used to develop biodegradable materials. Recent advancements and development in the field of natural polymers have opened up new possibilities for the rational engineering of natural gums and mucilage towards the expansion of functional excipients suitable for industrial and medical applications. This chapter highlights the potential sources of novel biodegradable polymers with recent expansion in the processing of different novel natural polymers to develop multifunctional excipients and valorization of waste biomass to produce biopolymers.