The cation composition of solutions and leachates from small-diameter laboratory soil columns was examined over a 23-week period after the addition of lime (0,3 and 6 t ha-') and/or nitrogen fertilizer (0 or 200 kg N ha-') to an acid soil (pH 4.2). Water was applied at regular intervals to the surface of the columns and 17 leachate samples collected. Initially, the pH of the leachate was high (6.6) in all treatments (including those without lime) but fell rapidly to approach a steady value of 3.8. Large losses of calcium occurred from all columns; the total equivalent amounts of lime lost ranged from 0.88 (no addition) to 2.38 (with added lime) t CaCO, ha-'. High concentrations of aluminium (181-325 p~)were present in leachates from all treatments; the addition of 200 kg N ha-' increased the leaching of Al by 94%; addition oflime also increased the amounts ofAl leached (by 52%).The pH of the soil solution (separated by centrifugation) was influenced by treatment, especially in the top 0-40 mm of the column. Aluminium concentration was related to pH, but the form of the relationship differed amongst the treatments.