Nonsuicidal Self-Injury (NSSI) is the deliberate inflicting of physical injury to one’s own body that is not due to accident or conscious attempt at suicide. This study examined NSSI, other excessive or potentially addictive behaviors, and borderline personality features. Undergraduates ( N = 151) completed the Deliberate Self Harm Inventory ( Gratz, 2001), the NEO PI-R ( Costa & McCrae, 1992), and the Shorter PROMIS Questionnaire (SPQ; Christo et al., 2003). The SPQ measures impulsive or compulsively motivated behavior, such as symptoms of substance use disorder, disordered eating, and involvement in dysfunctional intimate relationships. The sample was divided according to the number and type of NSSI incidents reported, and 41 (27%) of the students had self-injured, including 20 (13%) who had self-injured 10 or more times or who had practiced 3 or more methods of NSSI. These severe self-injurers had significantly elevated rates of alcohol and drug abuse, disordered eating, sexual compulsivity, and dysfunctional interpersonal relationships. They also scored higher on facets of Neuroticism, with lower scores on facets of Agreeableness and Conscientiousness. Personality facet profiles suggested that borderline personality features may be elevated among those who practice frequent and varied NSSI, and these results suggest involvement of maladaptive strategies for emotional self-regulation.