Project Summary The increasing pervasiveness of highly lethal fentanyl and fentanyl analogs in the illicit drug supply in the United States, including Ohio, has posed a substantial challenge for public health officials seeking interventions to reduce unintentional overdoses. Rapid fentanyl test strips, designed to test for the presence of fentanyl and some fentanyl analogs in urine samples, are increasingly being used off-label by people who use drugs to test illicit drugs for fentanyl before consumption. Recent research indicates that when people who use drugs receive a positive fentanyl test result, they are more likely to perform overdose risk reduction behaviors (e.g., using less of the drug). However, due to the emergent nature of this harm reduction strategy, peer- reviewed published research on this topic is very limited. We propose to test an intervention to provide fentanyl test strip education and distribution to people who use drugs in a subset of opioid overdose education and naloxone distribution sites in rural and urban counties in Ohio. The long-term goal of this research is the reduction of overdose-related morbidity and mortality in Ohio and nationally. The research objectives of this study are: 1) Determine the feasibility and acceptability of providing fentanyl test strip education and testing materials distribution in existing opioid overdose education and naloxone distribution programs; and 2) Determine if adding fentanyl test strip education and distribution to opioid overdose education and naloxone distribution programs decreases opioid overdose rates among people who use drugs. Using a two-arm cluster- randomized trial design, we will answer the research objectives by testing the following 3 specific aims: 1) Determine the perceived barriers and facilitating factors associated with incorporating fentanyl test strip education and distribution in existing opioid overdose education and naloxone distribution programs in rural and urban counties; 2) Test the hypothesis that people who use drugs who receive fentanyl test strip education and testing materials as part of an opioid overdose education and naloxone distribution program will have improved knowledge and self-efficacy regarding how to test drugs for fentanyl and strategies for lowering their risk of an opioid overdose; and 3) Test the hypothesis that individuals who receive fentanyl test strip education and testing materials as part of an opioid overdose education and naloxone distribution program will have a lower opioid overdose rate than individuals who receive opioid overdose education and naloxone distribution only (“usual practice”). Fentanyl test strip use is becoming more common, but research supporting the practice is limited. We will investigate the feasibility, acceptability, and associated benefits and harms of integrating fentanyl test strip education and distribution into existing opioid overdose education and naloxone distribution programs in rural and u...