Due to the complex and heterogeneous nature of obsessive–compulsive disorder (OCD), movement toward multimodal assessment has become necessary to more precisely understand the nature of the disorder and interrelations between symptom clusters. Thus, the present study utilized large undergraduate samples (total N = 800) to test the validity of six in vivo assessments of OC symptoms (i.e., one ordering/arranging task, two contamination fear/washing tasks, and three checking tasks). Associations between task-specific variables and self-reported symptom scores (as measured by the Obsessive–Compulsive Inventory–Revised [OCI-R]) were examined. The majority of the in vivo task variables (those presented in Studies 1-4) exhibited significant relationships with the corresponding OCI-R symptom subscale (i.e., ordering, washing, checking). However, many of the task variables demonstrated relationships with other OCI-R symptom subscales, as well. Some evidence for discriminant validity was found, as task variables were generally unrelated to past-week symptoms of depression or anxiety. While continued research is necessary to further establish the validity and utility of the tasks discussed in the current article, findings have implications for improving future empirical examination of OC symptoms.