The main purpose of the current study was to introduce the Spontaneous Expressions Recognition Test (SERT), a new thin-slice measure of emotion recognition for normative adults, and demonstrate its relative strengths for predicting positive interpersonal relationships. To explore this question, a semester-long longitudinal study was conducted. In this study, college students were randomly assigned to small research teams and worked together throughout the semester to conduct group research projects. Peer ratings of interpersonal relationships were collected at the end of the semester. The results provided preliminary support for the SERT, by demonstrating its relative strength for predicting positive interpersonal relationships.