PROJECT SUMMARY The goal of the proposed fellowship is to prepare the applicant for an independent research career focused on improving access to treatment for substance use disorders, especially those provided to assault-injured individuals; and to inform hospital-based violence intervention programs in preventing repeat violent injury. Violence and substance use have become public health crises in the US, demanding an urgent health care systems response. There are large gender and racial disparities in rates of violence among Black males. The prevalence of drug and alcohol use is immense in the US, and has been shown to be strongly associated with violence. However, there is limited research describing the complex relationship and intersection between drug/alcohol use and assault-related injury, especially recurrent injury. Additionally, limited studies have examined specific substance use types and violence victimization, specifically assault-related injuries requiring medical care and recurrent injury. Many of the relevant studies have relied on self-reported drug use rather than objective measures such as toxicology reports. Additionally, multiple studies have shown alcohol to be associated with violence and there is evidence to support the association between cocaine use and violence among adults, however results have been mixed regarding other drug types (e.g., marijuana, opioids, sedatives) and violence. The purpose of this study is to further understand patient (including drug/alcohol use & comorbid diagnoses), neighborhood, and injury-related factors associated with recurrent assault-related injury among adults aged 18 to 34 years who present to a hospital in Baltimore, MD with a blunt force, cutting/piercing, or firearm assault-related injury. The specific aims of this study are: Aim 1: Examine if patient (drug/alcohol use, comorbid diagnoses, demographics, and socioeconomic status), neighborhood (neighborhood violence, alcohol outlets, household education, household income, vacant houses, and drug arrests), and injury-related factors (injury severity score and mechanism of injury) at the time of presentation to the hospital for a blunt force, cutting/piercing, or firearm assault-related injury are predictive of recurrent assault-related injury. Aim 2: Describe experiences with violence and drug/alcohol use in individuals who have experienced a past year repeat assault-related injury and had a positive toxicology screen at the time of injury. Aim 3: Describe how the themes surrounding violence and drug/alcohol use revealed in Aim 2 further explain and extend the identified risk factors in Aim 1. This study is directly responsive to NIDA's Strategic Plan to determine the impact of drug use and addiction on individuals, families, peers, and society; specifically, the impact of substance use disorders on public health outcomes. The knowledge gained from this study will inform future interventions directed at improving access to effective ...