There are currently contradictory findings on whether frequency of having nightmares is related to psychopathology. Common drawbacks of many of the studies are the use of a single retrospective questionnaire to assess nightmare frequency and the measurement of stable traits rather than acute stress. In the present study 124 subjects (males, n = 32; females, n = 92; age 18-70 years) completed the EPQ-RS, the General Health Questionnaire-30, Gough's Creativity Scale and, over 14 days, a contemporaneous log of the incidence of nightmares. The 14-day log method produced a larger estimate of mean nightmare frequency (41.7 per year) than is common with retrospective measures; there was no significant difference in frequency of nightmares between males and females. Nightmare frequency correlated significantly with GHQ acute psychopathology (r(sp) = 0.26, p = 0.002), with comparable scores for females (r(sp) = 0.28) and males (r(sp) = 0.23). Females had significant correlations of nightmare frequency with age (r(sp) = -0.26, p=0.007), dream recall (r(sp) = 0.32, p=0.001) and EPQ-Lie score (r(sp) = -0.22, p = 0.020), whereas males did not: following regression analysis only females had significant determinants of nightmare frequency, these being GHQ acute psychopathology (beta = 0.300, p = 0.003) and age (beta = -0.232, p=0.020). Neither sex had significant correlations of nightmare frequency with creativity, extraversion, neuroticism or psychoticism. (C) 1999 Elsevier Science Ltd. All rights reserved.