The functions identified by the Discriminate Function Analysis (DFA) correctly classified 61 percent of cases, and identified the important roles of jealousy, dependency, attachment, and relationship aggression in harassment; differing responses to the measurement of these can theoretically distinguish between non-minor, and severe harassers. Findings show that of the total 132 reported engaging in 2 or more harassment acts and 148 reported being the victims of post break-up harassment on at least 2 occasions. The raw data consisted of participants’ responses to the dependency, attachment, and jealousy measures, as well as responses from themselves and their partners on the behavioral scales investigating relationship aggression and harassment. In attempting to classify non-harassers, minor, and severe harassers based on response measures of jealousy, dependency, attachment, perpetration, and victimization of relationship aggression, and harassment victimization, findings supported previous research. Evidence of more perpetration of physical aggression during their relationship for severe harassers than both minor and non-harassers in this study supports a relatively large body of research associating domestic violence and former-intimate stalking. There were more experiences found of being harassed and verbally victimized for harassers than were found in the other groups. Harassment victimization distinguished severe harassers from both minor and non-harassers, and verbal victimization experiences separated severe harassers from minor harassers in the current sample. Data were collected from 177 undergraduates from the University of Central Lancashire, Preston. Tables, references