This analysis explores the pattern of variation of the desired thermal sensation on the ASHRAE scale, applying the method of direct enquiry. Data are from studies of thermal comfort at university lectures and in selected dwellings. Respondents reported both their thermal sensation and the sensation they would have desired at that time. The data contain 868 comparisons of the actual and the desired sensation. On 57% of occasions the desired sensation was other than 'neutral'. The respondents did not always desire the same sensation, and the mean desired sensation differed systematically among the respondents. The mean desired sensation depended to some extent on the actual sensation, there being a positive correlation in the region from 'neutral' and 'warm' and a negative correlation outside this region. Sensations on the ASHRAE scale are shown to have more than one meaning. Adjusting the ASHRAE scale to allow for the desired sensation yields different distributions of thermal comfort and different group-optimum temperatures. The adjustment should therefore be applied whenever the ASHRAE scale is used. The implications for thermal simulation and for energy use in buildings are considered. (C) 2007 Elsevier B.V. All rights reserved.