Abstract
This article reports on a short-term longitudinal study exploring self-reported and behavioural procrastination of 298 German university students taking a 15-week statistics course. More specifically, associations between the Dark Triad traits and two self-report procrastination measures and one behavioural procrastination task (i.e., a comparison between actual and planned study time) were examined. Both psychopathy and narcissism were correlated with self-report and behavioural procrastination, but Machiavellianism was unrelated to either type of procrastination. Self-report and behavioural measures of procrastination were only weakly related. Our results suggest that behavioural and self-report measures of procrastination capture different aspects and processes of procrastination.