The agricultural sector is the main source of raw materials for biopolymers such as soy protein isolates (SPI), natural fibers, polylactic acid (PLA), polyhydroxybutyrates (PHBs), and many more. Over the years, the biopolymer sector has witnessed significant developments due to substantial investments that have been made in green technologies/processes. Apart from this, focus has also been given to improving the performance of the existing thermoplastic as well as thermoset polymers and synthetic fiber based composites. With the onset of green technology/process, agriculture has witnessed rapid transformation, which in turn has opened new avenues for the development of commonly available synthetic polymers, such as polyethylene from sugarcane. In fact, facilitating the commercialization of innovative processes/technologies developed in the laboratories is the first step. The second step is to take the products fabricated in the first step to the next level, i.e. the market. Lastly, demonstrating these products in real-life conditions is necessary for terming it as marketable products. The truth is that the development of biopolymer or nanomaterial based polymer-matrix composites are progressing slowly. This book is written to address some of the types of polymer-matrix composites as well as the performance of these composites through 11 original and very interesting Chapters. The use of biopolymer based composites has been greatly emphasized in Chapters 1 through 5 so as to reduce the carbon footprint. Chapters 6 through 9 are devoted to the performance of widely used thermoplastics, thermosets and conducting polymers. Lastly, the applications of natural fiber reinforced composites in automotive sectors as well as erosive wear performance are discussed in Chapters 9 through 11.