Rising rates of intravenous drug use (IDU) in Appalachia have necessitated new approaches to providing risk-reduction interventions in a manner which will be acceptable and accessible to specific at-risk populations-particularly those with limited access to traditional evidence-based interventions. Using the ADAPT-ITT framework, the overall goal of this study is to adapt an evidence-based HIV prevention intervention-the NIDA Standard-to meet the needs of rural drug-using women post-release from jail. Through a series of focus groups with rural incarcerated women, theater-testing with members of the target population, and iterative refinements with topical experts, we aimed to identify potential adaptations to content and context to improve the fit, feasibility, and acceptability of the NIDA Standard for this population using social media. Study findings confirmed the need for a preventive risk-reduction intervention targeting this population post-release. Adaptations to intervention content focused on adding, simplifying, and ensuring continuous access to content in the NIDA Standard. Adaptations to context included modifications to how the intervention will be delivered and by whom, including consideration of unique issues related to delivery using Facebook (such as privacy and confidentiality). The use of Facebook for delivery of the NIDA Standard may hold promise for increasing reach, acceptability, and feasibility of intervening with rural women with IDU released from jails, particularly when compared with traditional face-to-face sessions. With minor content adaptations to meet participant needs and preferences, plus multiple context adaptations to enhance accessibility and acceptability, the adapted NIDA Standard is intended to retain its original effectiveness while improving important implementation outcomes key to scaling-up and increasing public health impact. What is known about the topic? Injection drug use rates are high in rural Appalachia, and new approaches are needed to reduce the risk of HIV and HCV among injection drug using women involved in the criminal justice system in this region. While there are effective risk-reduction interventions for HIV and HCV, they are difficult to deliver in rural Appalachia and do not reach the women who need them. What does this paper add? This study describes the use of a systematic approach to improve the "fit" of an evidence-based intervention-the NIDA Standard-with the preferences and perspectives of injection drug using women involved with the justice system, aided by guidance from experts in a specific risk-reduction intervention (the NIDA Standard) and delivery of interventions using Facebook. Changes to the intervention to increase its acceptability and accessibility in this population included shifting delivery of the intervention to a closed Facebook group rather than in person; use of brief videos rather than written text to provide information; use of trusted local women to provide information through videos and Facebook posts; and inclusion of local information on community risk factors and resources. Implications for practice, research, or policy: The use of Facebook for delivery of the NIDA Standard holds promise for increasing reach, acceptability, and feasibility of risk reduction among rural injection drug using women released from jails. Next steps include testing the feasibility, acceptability, and effects of the adapted intervention in several rural Appalachian counties.