Technical Abstract: Challenges for current composite films in the food industry are the relatively high water vapor permeability and poor mechanical integrity of the edible films. Using nanoscience, new forms of tightly linked three dimensional networks can be developed to prevent migration of water in food products while improving film mechanical integrity. Incorporation of nanosize inclusions, fillers or emulsion particles, can provide higher surface interaction areas with the surrounding matrix. This study investigated the incorporation of microcrystalline cellulose and chitosan nanofillers into hydrox propyl methylcellulose films. The study also studied the effect of lipid particle size on the water vapor permeability of soy-based nanoemulsion films. The tensile, water vapor and oxygen permeability properties of edible films were significantly improved through the application of nanoscience to these systems.