Composites and nanocomposites are used in cases where long durability and strength of components are required; i.e., where high stress levels, erosion processes and multiphase environments are present, including the parts under collision and impact, the parts under rotating motion and erosion (like excavation drills in oil and gas wells). The first volume of this book aims to provide a guide for fabrication of new nanocomposites mainly based on carbon nanotubes and graphene. The main topics of this volume are: Application of Nano-powders for Formation of Metal Matrix of Composites, Conjugated Polymer Nanocomposites, Biopolymer Nanocomposites, Dental Nanocomposites, Graphene-based Nanocomposites for Electrochemical Energy Storage, Polymer/Filler Composites for Optical Diffuse Reflectors, Synthesis and Applications of LDH-Based Nanocomposites, Rubber—CNT Nanocomposites, Nanocomposite Fibers with Carbon Nanotubes, Fabrications of Graphene Based Nanocomposites for Electrochemical Sensing of Drug Molecules, Recent Advances in Graphene Metal Oxide Based Nanocomposites.