The physiological and psychological processes involved in odour perception are still not properly understood. It is not surprising therefore that researchers can experience difficulties when conducting consumer research for perfume development purposes. However, despite these problems, consumer perception and evaluation of alternative odour submissions for mass-marketed brands can be measured on a multi-cultural basis. Perfume selection should be determined by the role that the odour of a product plays in relation to the total expression of the brand's marketing concept and its relevance to consumer characteristics and needs. It is not simply a question of whether an odour submission is liked or disliked. The precise role the odour needs to play will depend on the specific product, brand, usage, user, geo-demographic and cultural context of the market for which the product is intended.