Cognitive techniques are becoming more widely established in the treatment of obsessive-compulsive disorder (OCD). This paper extends previous work by van Oppen and Arntz (1994, Behaviour Research and Therapy, 33, 79-87) on overestimation of threat and excessive responsibility by discussing other types of appraisals that may be involved in OCD, particularly when overt compulsions are absent. Examples are given of types of intervention that may be useful to correct faulty appraisals concerning the overestimation of the importance of thoughts such as thought-action fusion, excessive responsibility, perfectionistic concerns such as the need for absolute certainty, and expectations about anxiety and its consequences. Copyright (C) 1996 Elsevier Science Ltd.