Background: Enhancing access and use of evidence-based tobacco cessation treatments and eliminating tobacco-related health disparities are top national and VA health services priorities. The prevalence of tobacco use is greater among Veterans compared to non-Veterans. From 2010-2015, 29% of women and 21% of male Veterans reported current cigarette smoking. Evidence-based cessation treatments (EBCTs) such as, tobacco quitlines, behavioral counseling, and pharmacotherapy, are greatly underutilized by Veteran smokers. Gaps remain in reaching women Veterans and use of existing social support networks to enhance use of EBCTs and cessation among Veterans Innovation and Impact: This project is innovative for evaluating social support networks as a proactive outreach approach to enhance cessation treatment utilization among Veteran smokers. The role of social network influences and social support on successful smoking cessation is established. Based on Cohen’s theory of social support, our team developed a social support intervention for diverse family members, friends, and other adults who wanted to help a smoker quit. The intervention consists of written materials and a 1-call, 15-25 minute coaching session. It is expected to be especially beneficial for Veteran smokers who might not otherwise access cessation treatment. Because our prior VHA trials enrolled about 94% men and the higher smoking rates among women, we will oversample women to enroll an equal number of men and women smokers. Our study contributes to VA HSR&D’s priority initiatives for enhancing treatment access and women’s health and is significant because it will advance research on the role of partnering with Veterans’ families and/or important others to enhance access to VA healthcare and population-specific treatments, especially women Veterans. The potential reach and public health impact of an effective social support intervention for the Veteran tobacco user population is considerable. Specific Aims: (Aim 1) To evaluate the impact of the social support intervention on Veteran smokers’ use of EBCT, (Aim 2) To examine the effectiveness of the social support intervention on the biochemically confirmed 7-day point prevalence cigarette smoking abstinence, (Aim 3) To explore potential moderators (e.g., smoker gender, SP tobacco use status) of intervention effects on study outcomes, and (Aim 4) To conduct a process evaluation assessing implementation outcomes (reach, adoption, fidelity) of the social support intervention and multilevel factors that may influence implementation. Methodology: We will conduct a pragmatic randomized controlled trial (RCT) within the national VHA health system to evaluate the effectiveness of a social support intervention compared with a control condition on utilization of EBCT among VHA-enrolled smokers. Veteran smokers, regardless of level of readiness to quit, will be identified nationally using the VHA electronic health record and proactively recruited. In...