This project seeks to refine and assess OC-Go, a HIPAA-compliant web-based clinician portal and patient-side mobile application designed to increase patient adherence to evidence-based treatment (EBT) for Obsessive Compulsive Disorder (OCD), a common and impairing condition, and provider ability to effectively implement EBTs. OC-Go allows clinicians to create and push tailored assignments to patients on their mobile devices with an optimized user interface that includes patient accountability and support features. Accordingly, patients can be guided to do assignments by themselves between sessions with increased fidelity over the course of treatment. Once therapy assignments are created and shared to a crowd-sourced and curated public library, any clinician can assign any task to any patient for homework or in-session use with one touch. Use of OC-Go is expected to increase patient engagement, compliance, treatment efficiency, dissemination of EBTs, and therapist confidence and expertise.