The personality trait need for cognition (NFC) refers to individual differences in cognitive motivation and has proven to be an extraordinarily useful descriptor and predictor in the context of information processing. So far, NFC has been assessed via self-report. More recent research, however, accentuates the value of indirect measures, as they tap into implicit aspects of the personality self-concept and are assumed to provide incremental validity especially in predicting automatic aspects of behaviour. Therefore, in the present research, different NFC-Implicit Association Tests (IATs) were developed and pretested for psychometric properties. The final version was systematically tested for its predictive validity over and above the direct NFC measure based on a latent variable approach. The results provide evidence for a double dissociation model and suggest the NFC-IAT to exert its predictive value regarding the more spontaneous aspects of NFC-related behaviour, whereas the NFC scale was rather predictive for the more reflective aspects of behaviour. Moreover, the present research contributes to the understanding of construct-unrelated variance in personality IATs and offers valuable information for test development in the realm of personality IATs. Copyright © 2012 John Wiley & Sons, Ltd.