The scientific content of this symposium will focus on five areas: 1. High performance membrane materials for gas and vapor separation, 2. Fouling reduction for membranes used in liquid separations, 3. Membrane modification, 4. Novel materials for barrier packaging applications, and 5. Fuel cell membranes. These five session titles represent key scientific as well as technological areas for polymers and polymer-based composite materials used as high barrier films and coatings and as highly permeable gas and vapor separation membranes. Together, these sessions provide an integral set of complementary topics that will appeal to a broad cross section of polymer chemists and physicists, membrane scientists, chemical engineers, materials scientists, and polymer modeling experts from around the world.