The parent grant plans to examine the clinical and cost-effectiveness of cognitive-behavioral therapy (CBT) combined with contingency management (CM) in reducing problematic drinking in veterans who meet diagnostic criteria for alcohol use disorder (AUD). Research suggests that those with AUD and co-occurring suicidal thoughts and behaviors are more likely to respond poorly to AUD treatment and relapse on alcohol use. This is important, given that nearly half of those with AUD who present for AUD treatment report a history of suicidal behavior, and numerous studies indicate that those with co-occurring AUD and suicidal thoughts and behaviors tend to demonstrate more severe and chronic AUD symptoms. Despite the robust association between alcohol and suicide, and the extent that co-occurring suicidal thoughts and behaviors influences the presentation and treatment of AUD, little research has examined mechanisms underlying these associations. The proposed supplement would extend the parent grant study by testing the extent that ongoing suicidal thoughts and behaviors impact the progression of and response to CBT/CM for AUD, and examine if CBT/CM leads to reduction in suicide risk in veterans over time, thereby providing a further test of the clinical and cost effectiveness of CBT/CM for AUD (Aim 1). The proposed supplement would also involve secondary analyses of data from a recently conducted ecological momentary assessment (EMA) study on veterans at high-risk for suicide. This study, which was conducted over a 4-week period, involved veterans completing multiple brief surveys per day on a number of momentary variables, including daily alcohol use, momentary suicidal ideation, and other internal (e.g., affect) and contextual (e.g., daily stressors, interpersonal problems) variables. With these variables, the proposed supplement would use advanced longitudinal statistics to examine the extent that daily alcohol use leads to subsequent increase in suicidal thoughts, as well as if suicidal thoughts lead to increase in alcohol consumption, and explore moderators of these associations (Aim 2). While there have been several studies suggesting a dose response relationship between alcohol use and subsequent suicidal desires, the proposed supplement would be the first use EMA to examine the likely bidirectional and dynamic relationship between AUA and suicidal thoughts and behaviors. This will allow us to better understand how the co-occurring mental health problem of suicidal thoughts and behaviors perpetuates and worsens AUD symptoms in real life. Overall, improved understanding of longitudinal relationships between alcohol consumption and acute fluctuations in suicidal thoughts and behaviors in daily life and in the context of treatment significantly enhances the parent grant, and could be highly informative for the future modification and development of mobile health interventions with CBT/CM.