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The crystallinity of the clay mineral illite, which is a climatically sensitive parameter, was studied for palaeoclimatic inferences from a core raised from Nal Sarovar in western India. The changes in crystallinity of illite in the top 3m of the core showed that the climate was wetter than present from∼ 6.3-4.6 ka BP and was followed by a relatively dry phase which has continued up to the present. These palaeoclimatic observations are largely similar to those obtained from δ 13 C and C/N ratio variations in the top 3m of the core. From the deeper (> 3m) section, a wet spell around 50 ka BP was identified in an otherwise continuous spell of aridity between 7 and 73 ka BP. The presence of a red bed dated to-50 ka BP (depth 1285-1324 cm) also suggested that the climate was wet followed by dry conditions during this period.