The concept of emotional intelligence (EI) has drawn a great amount of scholarly interest in recent years; however, attempts to measure individual differences in this ability remain controversial. Although the Mayer–Salovey–Caruso Emotional Intelligence Test (MSCEIT) remains the flagship test of EI, no study has comprehensively examined the full interpretive argument tying variation in observed test performance to variation in the underlying ability. Employing a modern perspective on validation, this article reviews and synthesizes available evidence and discusses sources of concern at (...) every level of the interpretive argument. It is argued that a focus on causal explanation of observed variation in test performance would significantly improve the validity of the MSCEIT as a measure of EI. (shrink)