Human resource directorate employees of a large United Kingdom public hospital (N=36) completed an initial questionnaire and then participated in a daily diary study. The questionnaire included measures of affect and beliefs about high work demands' influence on affect and work performance. The diary included measures of affect, extent of high work demands, and daily beliefs, corresponding to those measured in the questionnaire. Participants were required to complete the diary twice daily, before and after work over a 2-week period. Measures of affect after work were associated with beliefs concerning work demands' influence on work performance and on affect measured after work. Beliefs about work demands measured in the questionnaire were associated with subsequent daily assessments of beliefs.