 The current work focuses on enhancing the mechanical properties of polymer-based composite materials made from agro-waste by treating the surfaces of natural fibers and natural particulates to increase hydrophobicity, which improves adhesion with the matrix. This review covers the physical properties of important NS and NPs, available chemical treatments, processing techniques, and mechanical properties of the resulting composite materials. This article was authored by Deepak Verma, Ken Lingo, and Wyn Stimmel.