Two experiments are reported using the odours of 5-alpha-androstan-3-one (androstanone) and, a control odour, aurantiol. Various measures of skin conductance (SC) were recorded and analysed and subjects also rated the odours using analogue scales. The first experiment involved comparisons between subjects who perceive the androstanone odour as pleasant and subjects who perceive it as unpleasant. A number of differences were shown between the two groups and also between androstanone and aurantiol. The results are interpreted as demonstrating the influence of cognitive factors that are found between male and female responses and also between the responses of the 'pleasant' and 'unpleasant' groups. The second experiment examined the SC response of subjects who displayed specific anosmia to the odour of androstanone. The results suggest that the concept of specific anosmia requires modification.