Pain Disengagement Training (Open Pilot)

Inclusion Criteria: 1. Outpatient adults (i.e., greater than or equal to 18) 2. Has self reported chronic musculoskeletal pain (i.e., pain persisting for at least 3 months) 3. Pain score greater than or equal to 4 (moderate) on the Numerical Rating Scale 4. Pain catastrophizing score greater than or equal to 20 on Pain Catastrophizing Scale 5. Willingness to engage in a writing-based intervention and self-reported ability to write or type for at least 30 minutes in a sitting 6. Received care at Massachusetts General Hospital 7. English verbal and writing fluency Exclusion Criteria: 1. Clinically significant change in therapy or medication in the past 3 months 2. Severe untreated mental health condition (e.g., psychosis) 3. Active suicidality with history of plan or current intent 4. Serious illness expected to worsen in the next 6 months (e.g., cancer) 5. Untreated substance use problem that, per patient's self-report, would interfere with the ability to complete the intervention.