 This work describes flax fiber reinforced polymeric composites with recent developments. The properties of flax fibers as well as advanced fiber treatments such as mercerization, silane treatment, acylation, peroxide treatment and coatings for the enhancement of flax slash matrix incompatibility are presented. The characteristic properties and characterizations of flax composites on various polymers including polypropylene, pp, and polylactic acid, epoxy, bio-epoxy, and biophonolic resin are discussed. A brief overview is also given on the recent nanotechnology applied in flax composites. This article was authored by Hershey Keshav Yankar, James Njaguna, Huijun Zhu, and others.