## 4 Discussion  
### Do Scents Affect Actual Customer Behavior in Retail Stores?  
Situated in the context of a growing interest in the field of aromachology, this paper has presented a systematic review of the available literature documenting the effects of using scents to create better customer experiences and affect their in-store behavior. Despite promising results from laboratory and controlled environment studies, suggesting that the addition of scents may affect product and store evaluations positively [27], the complexity and highly context-dependent nature of the sense of smell do not guarantee results will translate to actual retail environments. In fact, evidence from actual retail environments is remarkably limited, which only 20 studies meeting the inclusion criterion. This number is remarkably low in light of the fact that the relevance of scents for customer behavior has long been recognized [7; 14] and that the much larger number of laboratory-based studies published within the same period. This indicates that the application of aromachology in actual retail environments is still an under-researched area. This might possibly be due to practical difficulties in setting up field studies which require, on the one hand, researchers to step out of their familiar habits and, on the other, cooperative store managers interested and willing to let the study happen and share the data with the researchers.  
To date, much of the published research on the effects of aromachology has relied upon the S-O-R theoretical framework [7], the core of which suggests that a pleasant scent triggers a positive affective state in the consumer, which in turn evokes approach behaviors [28]. Another often considered framework is the thematic congruency of the scent with the store's offerings, on the premise that a match between the two is a necessary condition for an effect to occur [23; 31].  
While the literature offers some degree of support for both, neither the S-O-R nor the thematic congruency frameworks are consistently supported by the available data, suggesting that current theoretical explanations on the effects of scents on customer behavior may need updating. Yet, explanations beyond the notions of pleasantness and congruency were rarely considered in the literature. One exception was the study by [PERSON] and collaborators [29] that considered a processing fluency viewpoint, based on the work by [PERSON], [PERSON] and [PERSON] [50], suggesting that the effect of scents on behavior depends on the perceived complexity of the scent. The finding of that study, involving a home decor store, supported this, as they showed that, whilst keeping valence and familiarity constant, the addition of a simple scent (i.e., fewer components, easy to process) led to increased actual spending, whereas a more complex scent had no such effect. This indicates that there is still much we do not know, and that future research should, in particular, consider how scent properties other than pleasantness and congruency might influence customers' behaviors in ways that are relevant to the retail sector, and try to elucidate the causal mechanisms by which such properties might do so.