Abstract The paper considers the issues, raised by Koriat et al. (1973), of the consistency and reliability of measures of habituation currently used in personality research. It is argued that the problem of reliability is not as serious as Koriat et al. proposed and that specificity of measures of habituation is a theoretical rather than a methodological problem. It is proposed that ambiguity in the literature on the personality correlates of habituation is more likely to be due to the failure to consider the effects of stimulus conditions on habituation than to the problems of reliability and specificity.