Assertiveness is a background trait related to the temperament of an individual, thus influencing several aspects of everyday life. Research indicates that both under- and over-assertive behavior may have a negative impact on one's life, whereas the central position, positive assertiveness, seems to be most advantageous. This study utilized the 30-item PASS scale to observe differences in levels of positive assertiveness between students (high school, college, and university) and incarcerated individuals. As hypothesized, the three student groups scored significantly higher on positive assertiveness than the incarcerated group. A discriminant function analysis revealed that PASS could separate the incarcerated group from the student group using the factor scores from the five-factor model with 95.7% accuracy.