Divided or Single Exposure (DOSE) Study

Inclusion Criteria: * Aged 18 years of age or older * Currently receiving methadone for treatment of OUD for \>90 days and have been consuming the same dose for \>30 days * Have previously received a take-home dose of methadone as part of routine care * Willing to comply with study schedule * Report pain (specific definition blinded) * Have a cellular phone or be willing to carry phone provided by the study during one phase of the study Exclusion Criteria: * Pregnant * Presence of acute medical problem that requires immediate and intense medical management * Presence of a serious and unstable mental illness that interferes with provision of voluntary informed consent and/or adherence to study visits * Plans to leave methadone treatment during the study period * Maintained on a dose of methadone that would prevent effective splitting of doses * Currently receiving split doses of methadone * Currently receiving treatment for pain for which the split-dosing of methadone is judged by medical staff to be contraindicated or otherwise interfere with study conduct or integrity * Does not meet criteria for mild-severe disability (definition blinded)