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Organic sulphur in soil appeared to be stable in mildly alkaline solutions at 20°, and thus reagents such as bicarbonate or the sodium form of a chelating resin may be used for the partial extraction of organic sulphur in a chemically unmodified form. More complete extraction of organic sulphur from soil could be achieved by the use of sodium hydroxide solutions at pH 12.6, but degradation of humic acid sulphur to fulvic acid sulphur and conversion of organic sulphur to inorganic sulphur occurred in both hot and cold hydroxide solutions at this pH. A comparison of N : S ratios and percentages of reducible sulphur in soils and extracts suggested that none of the reagents studied extracted a sample of organic matter that was fully representative of the organic matter in soil. The results confirm that most of the sulphur in these surface soils is organic and that there is very little inorganic sulphate present. Sulphur that could be reduced by hydriodic acid occurred in compounds of both high and low molecular weight but data obtained from extraction with bicarbonate and the chelating resin suggested that much of the reducible sulphur occurred in the high molecular weight fraction of soil organic matter.