Externalizing disorders, as described by DSM-V (2013), are an empirically supported group of mental health conditions characterized by impulsiveness, antisocial behaviors, and disruptive conduct. These include Conduct Disorder (CD), Oppositional Defiant Disorder (ODD), Attention-Deficit/Hyperactivity Disorder (ADHD), and Impulse Control Disorders (ICDs). Symptoms often emerge during childhood or adolescence, when brain development is still ongoing. A prematurely-developed prefrontal cortex, paired with reward-seeking and emotional responses in youth, can contribute to impulsive behaviors and limited ability to predict the consequences of one’s actions (Casey, Jones, & Hare, 2008). Compared to females, males tend to be diagnosed with higher rates of externalizing disorders (Kerr, Reinke, & Eddy, 2013), which may place them at higher risk for engaging in risky and/or harmful behaviors. Research indicates that youth with externalizing disorders engage in a number of risky/harmful behaviors that could have negative consequences. A meta-analysis by Allely (2014) suggests that certain externalizing disorders, such as ADHD, may be a risk factor for self-harm behaviors in child, adolescent, and adult populations. Further, those with externalizing disorders in late childhood tend to have co-morbid depression and are more prone to suicidal ideation and suicide attempts during late adolescence and early adulthood (Kerr, Reinke, & Eddy, 2013). Others have also found a strong connection between externalizing disorders and suicidal behaviors among youth (Beautrais, 2000; Goldston et al., 1998; Hills, Cox, McWilliams, & Sareen, 2005; Verona & colleagues, 2000; 2001; 2004). Moreover, externalizing disorders, such as ADHD or CD, are correlated with sexual offending behaviors, which may be a result of sexual disinhibition (Kafka, 2012). While diverse, persons who have engaged in sexually abusive behavior often evidence antisocial behaviors and diagnoses of ADHD and CD (Prendergast, 2004; Shields, 1995). Grant et al. (2009) additionally indicated that the presence of trauma may also contribute to behavioral problems that resemble externalizing disorders. The current study aims to investigate male adolescents with and without externalizing disorders (i.e., ADHD, ODD, CD, and ICDs) by investigating a sample of youth in a residential treatment facility for sexually abusive behaviors (N = 295). Data related to adolescents’ self-harm behaviors, suicidal ideation and/or attempts, sexual offending behaviors, arrest histories, and diagnostic mental health histories were gathered from archival records. Within the sample, 234 participants were diagnosed with at least one externalizing disorder, including ADHD (n = 209), ODD (n = 91), CD (n = 102), and ICDs (n = 50). Chi-square analyses and one-way ANOVAs will be conducted to explore relationships among externalizing disorders, presence and frequency of self-harm behaviors and/or suicide attempts, frequency and types of sexual offenses committed, and frequency and types of arrest. Presence of PTSD diagnoses and Adverse Childhood Experiences (ACE) will also be taken into consideration, as previous literature suggests that early sexual, physical, and emotional trauma may also contribute to behavioral problems and sexual offending behaviors in adolescents (Grant et al., 2009). The goal of the current study is to fill gaps within the literature by identifying areas of concern among adolescents with externalizing disorders. The findings from the current study will be discussed in terms of clinical implications regarding risk reduction, prevention, and treatment.