Biopolymers are generally considered eco-friendly alternatives to petrochemical polymers due to their renewable feedstock and biodegradability. However, the farming practices used to grow these feedstocks carry significant environmental burdens, and the production energy can be higher than for petrochemical polymers. Biobased polymers have become feasible alternatives to traditional petroleum-based plastics. However, the factors that influence the sustainability of biobased polymers are oft en unclear. This chapter reviews the published life cycle assessments (LCAs) and commonly used LCA databases that quantify the environmental sustainability of biobased polymers and summarizes the range of findings reported within the literature. LCA is discussed as a means for quantifying environmental impacts for the product from its cradle, or raw materials extraction, to the grave, or end of life. The results of LCAs from existing databases as well as the peer-reviewed literature allow for the comparison of environmental impacts. Recently, interest in composite manufacturing has shift ed towards the use of natural fibers as reinforcement because of their environmental benefits. The use of a biodegradable matrix is worth considering since this would result in a completely biodegradable composite. In order to assess the most suitable matrix polymer, one must know the properties of the available polymers. This chapter reviews the importance of biopolymers in the present decade and also discusses the preparation of biopolymers and its properties. © 2015 by Scrivener Publishing LLC. All rights reserved.