The effect of parameters such as pressure-drop, column length, particle size and extra-column effects arising from the detector and inlet system, on minimum analysis time in a packed column liquid chromatography apparatus has been studied. Expressions have been derived which relate these parameters to the analysis time and allow the optimum and limiting parametric values to be estimated. In particular contributions to the bandwidth from several inlet systems and a potentially useful detector have been experimentally measured. It has been shown experimentally that the extent to which the particle size of the column effect can profitably be decreased is ultimately limited by phenomena which change the packing structure. These results suggest that analysis times of minutes should be possible in liquid chromatography in columns—even where relatively small separation factors are involved since the values of the various parameters which are needed to do so fall within a practically attainable range.