This volume contains the fourteen papers presented at the NATO-sponsored Ad­ vanced Research Workshop on the 'Status and Future Developments in the Study of Transport Properties' held in Porto Carras, Halkidiki, Greece from May 29 to May 31, 1991. The Workshop was organised to provide a forum for the discussion among prac­ titioners of the state-of-the-art in the treatment of the macroscopic, non-equilibrium properties of gases. The macroscopic quantities considered all arise as a result of the pairwise interactions of molecules in states perturbed from an equilibrium, Maxwellian distribution. The non-equilibrium properties of gases have been studied in detail for well over a century following the formulation of the Boltzmann equation in 1872. Since then the range of phenomena amenable to experimental study has expanded greatly from the properties characteristic of a bulk, non-uniform gas, such as the viscosity and thermal conductivity, to the study of differential scattering cross-sections in molecular beams at thermal energies, to studies of spectral-line widths of individual molecules and of Van der Waals complexes and even further. The common thread linking all of these studies is found in the corresponding theory which relates them all to the potential energy function describing the interaction of pairs of molecules. Thus, accompanying the experimental development there has been a corresponding improvement in the theoretical formulation of the quantities characterising the various phenomena.