1. Introduction and Perspective D.R. Paul and Y.P. Yampolskii 2. Mechanisms and Theories for Sorption and Diffusion of Gases in Polymers J.H. Petropoulos 3. Relationships between Structure and Transport Properties for Polymers with Aromatic Backbones M.R. Pixton and D.R. Paul 4. Relationships between Structure and Transport Properties for High Free Volume Polymeric Materials N.A. Plat nd Y.P. Yampolskii 5. Membrane Formation for Gas Separation Processes W.J. Koros and I. Pinnau 6. Facilitated and Active Transport E.L. Cussler 7. Unusual Membrane Processes- Non-Steady-State Regimes, Nonhomogeneous, and Moving Membranes I.N. Beckman 8. Membrane Separation of Organic Vapors from Gas Streams R.W. Baker and J.G. Wijmans 9. Industrial Applications of Membranes for Gas Separation in Japan T. Nakagawa 10. Commercial and Practical Aspects of Gas Separation Membranes J.M.S. Henis 11. Comparison of Membranes with Other Gas Separation Technologies R. Prasad, R.L. Shaner, and K. Doshi