Clients in treatment for Opioid Use Disorders, particularly those in medication assisted treatment have been found to have extremely high rates of co-occurring gambling disorder. This online training will review the research on the co-occurrence of gambling disorder and opioid use disorder, focusing on both quantitative and qualitative research that has sought to understand this connection. Transcripts from clients in medication assisted treatment will be used to illustrate the role gambling plays in their lives and recoveries. Strategies for screening and treating gambling issues among those in treatment for opioid use disorders will be discussed.