question: Introduction Contingency Management (CM) is one of the most effective interventions for persons with opioid use disorder, but one of the least available interventions in community settings, including opioid treatment programs. Project MIMIC is a NIDA-funded cluster randomized trial that is measuring CM implementation and sustainment across 30 opioid treatment programs in the New England region of the United States. The advent of the COVID-19 pandemic occurred in the midst of Project MIMIC's first cohort of eight opioid treatment programs, presenting a natural opportunity to document and analyze novel challenges to CM sustainment. Utilizing both quantitative and qualitative data collection, we aimed to identify both COVID-related barriers to CM sustainment and innovative workflow strategies to mitigate these barriers. Methods Quantitative analysis was conducted using data collected from a study-specific CM tracker tool on various CM implementation metrics over three distinct, successive time intervals: prior to COVID-19 social distancing orders with active support;during COVID-19 social distancing orders with active support;and during COVID-19 social distancing orders after removal of support. Semi-structured qualitative interviews were conducted with a representative from each of the eight opioid treatment programs. Using a reflexive team approach, transcripts were coded by independent raters to identify both COVID-related barriers to sustainment and innovative workflow adaptations. Results Quantitative data revealed a substantial decrease in the number of CM encounters following social distancing orders from 31.8 encounters weekly across eight programs to 6.9 encounters weekly across five programs. A further decline to 1.8 weekly encounters across three programs was observed after implementation support was removed. Four COVID-related barriers were identified via thematic analysis: fear of contagion;difficulty engaging patients remotely;challenges re-defining the CM attendance target due to changing regulations;and staff shortages. Potential adjustments discussed to help address one or more of these barriers included an electronic prize generator;use of technology to promote engagement;brief individual remote check-ins;and expansion of training to non-counseling staff. Conclusion Although CM implementation challenges emerged during the pandemic, associated workflow adaptations also emerged. The feedback solicited in this study will inform multi-level strategies to aid with CM sustainment post-pandemic.