The present study investigated the role of standard setting by examining the differences in cognitive, affective, and behavioural responses to completing a task for adaptive and maladaptive perfectionists, and the impact of manipulating the expected standards of a task on the evaluation of performance standards. Groups of adaptive, maladaptive, and non-perfectionist participants completed a 15-min anagram task. Levels of positive and negative mood, task anxiety, self-efficacy, and threat appraisals were assessed. Results showed that conditions which involved a high expected standard of performance (i.e., high evaluative threat) were detrimental for maladaptive perfectionists as demonstrated in their higher levels of emotional distress, greater endorsement in dysfunctional thinking, and lower levels of persistence on insolvable anagrams, while adaptive perfectionists and non-perfectionists showed no significant differences in patterns of responding, irrespective of the expected standard. However, adaptive perfectionists were significantly more persistent on insolvable anagrams when under conditions of high evaluative threat. These findings provide support to existing theories of perfectionism and are discussed in terms of the way that the setting and attaining of standards for a task may play across adaptive and maladaptive dimensions of perfectionism. Both clinical implications of the present findings and directions for future research are also explored.