This study investigated the discriminant, criterion and incremental validity of an ability measure of Emotional Intelligence (EI). High school students (N = 77) took the Mayer-Salovey-Caruso Emotional Intelligence Test - Spanish Version (MSCEIT V. 2.0, 2002), a measure of Big Five personality traits (BFQ; Caprara, Barbanelli, & Borgogni , 1993), an General Intelligence test (IGF-r 5; Yuste, 2002), and a social competence inventory (AECS; Moraleda, González, & García-Gallo, 1998). Students' academic grades also were obtained from official school records at the end of the school year. As predicted, the MSCEIT was discriminable from well-established measures of personality and intelligence. The test was also moderately related to social competence and predicted students' final grades. Most of the findings remained significant after personality and academic intelligence were statistically controlled. The potential utility of EI in the context of academic institutions is discussed.