This book focusses on processing, properties of various types of composite materials, as well as their environmental engineering applications. This book examines the current state of art, new challenges, and opportunities of composites in environmental engineering. The chapters in this book covers nearly every topic related to composites in environmental engineering in four broad perspectives:  (i) classification of composites (ii) green/hybrid synthesis and characterization of nano and biocomposites (iii) processing of composite materials (iv) state-of–the-art in fabricating the composites - nano and biocomposites - for environmental applications.