The mere exposure effect (MEE) was first identified by Zajonc (1968:1) who observed that, "the mere repeated exposure of the individual to a stimulus is a sufficient condition for the enhancement of his attitude towards it. By 'mere exposure' is meant a condition which just makes the given stimulus accessible to the individual's perception". Since then, this robust experimental phenomenon has been demonstrated in over 300 studies in the psychology literature; most often in relation to changes in affective response to abstract, novel stimuli (for reviews see Harrison, 1977; Bornstein, 1989; Bornstein and Craver-Lemley, 2004). Given that it provides a theoretical and empirical framework within which to explore and explain the attitudinal effects of repeated, fleeting communication that receives minimal attention and elaboration, it has been deemed to be most important to the fields of marketing and consumer behaviour (Bornstein and Craver-Lemley, 2004). Indeed, it may be considered to be particularly relevant in the context of a contemporary consumption environment that is largely characterised by a proliferation of brands, media and messages, the fragmentation of traditional channels and audiences, and thus low levels of consumer attention, engagement and involvement. Under such conditions, it may be argued that the MEE constitutes a potentially important means by which to study, understand and shape the effects of simple, repeated brand communication. However, it is important to acknowledge that the nature of marketing stimuli, consumption-based evaluation and decision-making, and the context in which this occurs is often quite different from the laboratory conditions in which the MEE has been demonstrated in psychological research. As such, there is a need to robustly test the assumptions that may be drawn from four decades of experimental research in psychology before they can be confidently applied in the specific domain of marketing. At the same time, however, it is important to stress that the MEE represents just one of an array of potential influences on real-world consumer processing and decisionmaking. Furthermore, and within the constraints of current methodological alternatives, it is arguably impossible to isolate, identify and examine this phenomenon alone in such a complex natural environment. As such, it is necessary to take an incremental approach to the extension of abstract psychological research in the marketing domain; to carefully bridge the gap between pure psychological understanding and that which relates specifically to consumer behaviour. A relatively small body of experimental marketing research has endeavoured to begin this process; although (it will be argued) current findings regarding the occurrence and nature of the marketing-based MEE are somewhat limited, often equivocal and subject to some important limitations. The purpose of this thesis, therefore, is to underpin and extend the incremental development of first-principles mere exposure research in the marketing domain. To this end, it provides a comprehensive review of both the state of current psychological understanding and the degree to which it has been applied in the marketing literature, prior to a robust examination of the existence, size and nature of this phenomenon in a marketing context. This is achieved by marrying the highly controlled experimental methods of psychological mere exposure research with the use of typical marketing stimuli, brand-related evaluation and a relatively large sample (as is common in the broader field of marketing research but not, as yet, with regard to the MEE in particular). The results of this empirical work are somewhat surprising and challenge previous assumptions regarding the influence of recognition memory and the direction of the exposure-induced affect-bias. Taken together, they support a 'dual-processing' model of mere exposure, incorporating two forms of the MEE that are underpinned by the processes of implicit and explicit memory respectively. This model has potentially significant implications for theory, practice and further research in the fields of both psychology and marketing; all of which are discussed in the final part of the thesis.