A parameter estimation approach that combines a numerical code for unsaturated flow with a nonlinear optimization method was used to analyze horizontal infiltration data for Columbia silt loam and Hesperia sandy loam. The data were previously investigated byNielsen et al. (1962)using the analytical method ofBruce and Klute (1956). As with the original analysis, water content profiles at the different times could be analyzed accurately in a simultaneous fashion only when the applied pressure head at the column boundary was close to saturation (−0.02 m). For much lower boundary pressures (−0.50 and −1.00 m), water content profiles for the different times had to be analyzed independently. Excellent agreement was obtained between diffusivities calculated from the same water content profiles using either the analytical method of Bruce and Klute or the numerical parameter estimation technique. However, in addition to diffusivities, the numerical parameter estimation analysis also provided estimates of the entire soil-water retention and hydraulic conductivity functions. Numerical analysis of the experimental data produced functional forms of the hydraulic properties, compared with point values, when using the analytical analysis.