The Institute of Gas Technology (IGT) is conducting tests on the effect of pore and confining pressure on the absolute and relative permeability of Western tight sandstone. Cores from the Canyon Largo No. 256 Well in the San Juan Basin, Dakota Formation, Farmington, New Mexico, and the Mobil F3l-l3G Well in the Piceance Basin, Zones 3 and 6, Rio Blanco County, Colorado, are being examined. Steady state flow and pressure pulse decay tests have been conducted at pore pressures up to 4700 psi and confining pressures up to 9700 psi. Relative gas permeability values have been measured at different levels of water saturation and compared with an earlier empirical correlation proposed by Corey. The effect of confining pressure on tight sandstone was studied and results were found to conform to the observations of earlier investigators.