Inclusion Criteria:  Meet DSM5 criteria for OUD and receiving stable (i.e., unchanged in 2 weeks) dose of OAT (i.e., buprenorphine or methadone) in VACHS outpatient addiction clinic Diagnosis of musculoskeletal pain or report of moderate pain intensity (i.e., 4 out of 10) that has persisted for more than 3 months Report at least moderate pain interference past week (i.e., 4/10 on the either of the two pain interference items on the PEG) Self-reported ability to walk 1 block Access to a mobile phone with active data plan  Exclusion Criteria:  Untreated major psychiatric disorders (e.g., bipolar disorder, psychotic disorder) Current (i.e., past month) active suicidal ideation Substance use disorder requiring inpatient detoxification Currently engaged in CBT for chronic pain treatment Planned surgical intervention for pain