Cognitive ability and personality have long played central roles in the investigation of determinants of human performance. Recently, the construct of emotional intelligence (EI) has emerged in the popular literature as an additional explanatory concept for human behavior and performance. The ability conceptualization of EI proposed by Mayer, Salovey, and their colleagues involves the perception, assimilation, comprehension, and management of emotions. Its proponents consider it to be distinct from either general cognitive ability (g) or personality. The purpose of this study was to investigate the construct validity of EI by examining its relations to g and the Big Five personality dimensions of Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. The observed correlation between scores on the Wonderlic Personnel Test (a measure of g) and EI was r=0.454. A regression model that included three predictors representing g, the Big Five dimension of Agreeableness, and sex showed an R of 0.617. After correction for unreliability the multiple correlation became 0.806, showing a strong relationship. Based on these results, we question the uniqueness of EI as a construct and conclude that its potential for advancing our understanding of human performance may be limited. Implications and suggestions for future studies are discussed.