Chapter 3 reviews different theories of memory and also applications of these theories to research on advertising. We criticize that traditional measures of advertising effectiveness are based on recall or recognition of advertisements. Because recollection of the content of advertisements may be unrelated to product evaluations formed on the basis of these advertisements, memory measures are not valid measure of advertising effectiveness. Advertising increases the ease and speed with which brand names are retrieved from memory (i.e. cognitive accessibility), which influences the inclusion of a brand in a consumer’s consideration set (i.e. brands brought to mind in a particular choice situation). Because consumers are exposed to a multitude of competing advertisements that compete for their attention (advertising clutter), advertisers have developed several strategies to combat this, such as the use of retrieval cues, ad repetition and placing the ad in an advantaged position within a block of advertisements. As a final point, we discuss evidence that advertising can distort consumer memory of products. Since brand images are at least partly the product of advertising and since brand images are assumed to influence product evaluation (brand equity), these findings should not be unexpected.