Thirteen checkers and twelve noncheckers, identified on the basis of their responses to the checking subscale of the Maudsley Obsessional-Compulsive Inventory (MOCI; Rachman and Hodgson, 1980), were recruited from a sample of 99 consecutive admissions to the outpatient department of a community mental health center. Consistent with our previous research with nonclinical samples of college students (Sher et al.,1983, 1984), checkers were found to show deficits in memory, especially recall for recently completed actions, compared to noncheckers. This result demonstrates the replicability of our previous findings across different types of samples and implicates deficits in memory for actions as a potentially important determinant of checking behavior. Assessment of spontaneous imagery associated with the anamnestic process suggested that checkers utilized less imagery, especially visual imagery, when recalling biographical information. Additional measures collected at the time of testing indicated that checkers were more neurotic and reported more psychological distress than noncheckers.