Relevance has been applied to various conditions in the marketing literature but no single definition has been developed. A single clear definition will be helpful to researchers investigating relevance in the marketing and consumer behavior fields. Confusion also exists in the literature regarding to what extent a symbolic visual in an advertisement is relevant. Many researchers are also calling for empirical evidence of a linkage between relevance and response through a theoretical measure of relevance. The central theory used in this dissertation is Sperber and Wilson's (1995) theory of relevance (TOR). TOR can help researchers and marketing managers by explaining how consumers may interpret visuals in advertising. TOR explains why some visuals thought to be unconnected with the product become relevant in advertising. This study makes the assertion that TOR has been underutilized and even ignored by some researchers in past marketing literature. Thus, TOR is used to provide greater explanatory power of consumers' interpretation and response to advertising visuals than what is currently realized by researchers and marketing managers. A reliable measure of relevance was developed using TOR as a foundation. Experiments were conducted to empirically test TOR and support was found for most aspects of the theory. This …