This study will address questions of fundamental clinical significance including: (1) whether OCD patients maintained on long term SRIs can be discontinued without symptom exacerbation, (2) whether trans-diagnostic cognitive-behavioral treatment will reduce worsening following discontinuation compared to Taper and Monitoring, and (3) whether predictors of successful SRI discontinuation can be identified.

Inclusion Criteria:

1. 18 or older
2. Presence of mild to moderate OCD symptoms
3. Patient's treating clinician agrees that SRI discontinuation is clinically appropriate
4. Adequate trial of SRI (≥10 weeks) in the current treatment episode
5. Maintenance on SRI dose that has not increased due to significant clinical worsening in the two years prior to enrollment
6. English speaking

Exclusion Criteria:

1. Clinically significant suicidality or a suicide attempt within the past year
2. Presence of any clinical features warranting a higher level of care (partial or inpatient hospitalization)
3. Current or recent (past 6 months) alcohol or drug dependence or abuse
4. Current or past psychotic disorder or bipolar disorder
5. Moderate to severe depression, as indicated by a Hamilton Rating Scale for Depression (HRSD) (17-item) ≥ 14 or recent major depressive episode (past 6 months)
6. History of severe OCD (YBOCS ≥ 28)
7. Prior adverse experience with SRI discontinuation
8. Primary compulsive hoarding
9. Cognitive impairment that would interfere with study participation
10. Concomitant psychosocial treatment w/ proven efficacy in the treatment of OCD
11. Previous adequate trial of exposure-based treatment (e.g., history of 12 or more sessions) in past 5 years
12. Use of non-SRI psychotropic medications for OCD in the 3 months prior to enrollment.