On the basis of the authors' own research it is suggested boredom may be viewed as having cognitive and affective components. The cognitive component is subjective monotony and the affective component is a high level of frustration. An attempt is made to integrate the evidence supporting this view of boredom with other evidence from the literature to present an integrated model of boredom in which the roles of personality, situational and task characteristics influencing boredom are outlined. Psychophysiological changes occurring during the performance of boring tasks are examined. It is argued that the nature and extent of changes in heart rate and heart-rate variability are not a consequence of boredom but of a task feature (mental load). It is concluded that no clear psychophysiological component of boredom can be detected at present.