Individuals who outshine others may experience distress if their performance poses an interpersonal threat. A scenario-based measure, the Test of Responses to Outperforming Others (TROO), was developed to assess positive and negative responses to outperformance among undergraduates. Three studies provided preliminary validation. Studies 2 and 3 examined personality correlates. Narcissism emerged as a robust predictor of positive emotion on the TROO and anger in response to scenarios involving hostile provocation. Sociotropy consistently predicted greater distress on the TROO. Of importance, sociotropy's role could not be reduced to factors such as self-esteem, depressive symptoms, the Big Five, gender, or social desirability.