Abstract: A biaxially-oriented polypropylene (BOPP) film with improved barrier properties, and a method of making the film are provided. The MVTR of a multi-layer BOPP film is improved by blending wax in the core layer resin, and providing a polyolefin cap layer on each side of the core layer. Significant additional improvements are seen when the film is heated at a temperature below the melting point of the core layer resin, below the distortion temperature of the film, and above the melting point of the wax for a time generally extending from at least five minutes to several hours or more in length, depending on the temperature.