Many laboratory displacement tests have been performed to study factors affecting relative performed to study factors affecting relative permeability curves, residual saturations, and shape permeability curves, residual saturations, and shape of recovery curves. Three sintered artificial porous materials and pure fluid mixtures have been used for this systematic study. The factors were interfacial tension, the viscosity and the velocity of the fluids (in the dimensionless group σ/µv), the wettability, and the viscosity ratio. The results can be used as guidelines for research on recovery processes. Introduction: Waterflooding is by far the most common secondary recovery technique. Several processes (polymer injection, surfactant injection, hot water injection, etc.) attempt to improve sweep efficiency by affecting some of the factors involved in the displacement process. For orienting research on these processes, process. For orienting research on these processes, a good knowledge of how these parameters affect local displacement efficiency and over-all sweep efficiency in the reservoir is required. We present here an attempt to understand the effects of such parameters: (1) at the microscopic level on the shape of relative permeability curves and the values of final saturations obtained by flooding, and (2) at the macroscopic level, on the behavior of one-dimensional displacement. Effects of the morphology of the porous medium were not included in this study. We mainly examined the effects of fluid properties on fluid displacement in only three specific porous media. These three artificial sintered media were made of Teflon, stainless steel and alumina. For the following reasons they were very well suited to the systematic investigation undertaken: (1) they are homogeneous and so the results are not subject to macroscopic heterogeneity effects; (2) they are identical in the same series, thus permitting the results to be compared from one experiment to another (3) their constant and well-defined chemical composition makes it possible to perform wettability measurements outside the porous medium; (4) they are consolidated like most of reservoir rocks; (5) they have good mechanical properties and so can be washed successively without being altered and (6) the three media used correspond to three possible cases of wettability, i.e., Teflon is strongly oil-wet, alumina is strongly water wet, and stainless steel may have intermediate wettability depending on the fluids considered. Some of our results reported here (concerning experiments with Teflon at a viscosity ratio of one) were presented earlier.