This study explored the relationships between individuals' ability to tolerate emotional distress to their tendency to worry excessively, the amount of imagery they experience during worrying, and the concreteness of their worrisome thought. A group of 119 university students completed a thought-listing task recording their most severe current worry, estimated the amount of imagery and verbal thought during this worry episode, and completed questionnaires assessing their worry proneness, negative effect, and ability to tolerate emotional distress. The concreteness of thought-listed worry episodes was rated by independent judges. Consistent with expectations, lower distress tolerance was associated with more worrying, even when levels of negative affect were statistically controlled for. Excessive worriers also reported lower levels of imagery, but imagery and distress tolerance were unrelated. The findings concerning concreteness were in the opposite direction to those expected: more excessive worrying and lower distress tolerance were associated with more concreteness of worrisome thought. The results are consistent with avoidance theory, but future research is needed to investigate the mechanisms by which low distress tolerance may contribute to excessive worrying.