Preference formation involves comparing brands on specific attributes (attribute-based processing) or in terms of overall evaluations (attitude-based processing). When consumers engage in an attribute-based comparison process, the unique attributes of the focal subject brand are weighed heavily, whereas the unique attributes of the less focal referent brand are neglected. This is because the attributes of the subject are mapped onto the attributes of the referent, rather than vice versa. This direction-of-comparison effect is reduced when consumers engage in attitude-based processing or when high involvement increases motivation to process accessible attributes more thoroughly and systematically. The present research investigates a personality variable, need for cognition, that increases the likelihood of attribute-based (i.e., high need for cognition individuals) versus attitude-based processing (i.e., low need for cognition individuals) and therefore, also affects the magnitude of the direction-of-comparison effect. The direction-of-comparison effect is observed only when attribute-based processing is likely (i.e., when need for cognition is high) and when thorough and systematic processing is unlikely (i.e., when involvement is low). Mediational analyses involving attribute recall and a useful new measure of analytic versus intuitive processing support this dual-process model.