The long-term goal of this research proposal is to increase effective and successful strategies for management of opioid use disorder (OUD) among US veterans. Compared to the general US population, veterans are at a higher risk for substance dependence due to additional risk factors such as post-traumatic stress disorder, chronic pain, sleep issues, and use of other substances such as alcohol or sedatives. Medication-assisted therapies (MAT) serve as an effective treatment option for those with OUD and combines a pharmacological treatment approach through opioid agonist treatment such as buprenorphine or buprenorphine/naloxone with psychological therapies. Retention in MAT with buprenorphine has long-term benefits for veterans including decreased mortality, illicit opiate use and criminal activity, and increased ability to obtain gainful employment. The key challenge, however, is ensuring appropriate access to care and delivery of these approaches to US veterans. Veterans more often live in rural areas where the burden of the opioid epidemic has significantly escalated over the last 20 years. Additionally, access to treatment with MAT is a challenge in rural areas, which suggests a significant proportion of veterans may not be receiving the care they need in a timely fashion. For those who do receive MAT, long-term treatment retention is a marker of success; however, previous studies have shown that only 35% of veterans with OUD receive medication-assisted therapies (MAT) and nearly 40% discontinue MAT within the first year of treatment initiation. In other chronic disease models, treatment retention and adherence improve when the patient and provider have an existing therapeutic history. Additionally, telehealth services have expanded considerably in recent years for mental health care, and has been recently been adopted for MAT and OUD management. The objective is to identify the relationships between therapeutic relationships, telehealth, treatment retention, and mortality. The central hypothesis is that existing therapeutic relationships and telehealth utilization to overcome geographic disparities in buprenorphine access will improve treatment retention for OUD, which will subsequently reduce suicide- and overdose-related deaths. This is a retrospective cohort study using currently-available administrative data from the Veterans Health Administration (VHA) Corporate Data Warehouse. The first aim of this study is to evaluate whether therapeutic history established between veterans and their buprenorphine providers affect treatment retention. The second aim is to evaluate telehealth services utilized during buprenorphine treatment within the VHA on treatment retention for patients. Finally, the third aim is to evaluate whether treatment retention is associated with suicide and overdose mortality rates, which will be obtained from the National Death Index. The objectives of this study are consistent with the priorities of the National Institute...