Peer Activate: Trial of Peer-Delivered Behavioral Activation for Methadone Adherence

Inclusion Criteria: * Initiated methadone at the study site in the past three months (and no less than two weeks prior to study enrollment) or demonstrated challenges with methadone adherence in the past three months as indicated by one or more of the following: a) at least one missing take-home bottle at the time of bottle return; b) screened negative for methadone in routinely administered clinic urinalysis tests; c) transitioned from an extended take-home bottle schedule to daily dosing schedule; or d) at least one missed methadone dose in the past 3 months as identified through clinic records * Minimum of 18 years old Exclusion Criteria: * Demonstrating active, unstable or untreated psychiatric symptoms, including mania and/or psychosis that would interfere with study participation * Inability to understand the study and provide informed consent in English * Positive pregnancy status at enrollment