When Are Broader Brands Stronger Brands? An Accessibility Perspective on the Success of Brand Extensions

Afundamental goal of brand extension research has been to assess the attractiveness of a brand extension opportunity (Aaker and Keller 1990; Boush and Loken 1991). As the research stream has matured, the emphasis has shifted from examining individual extensions to studying the effect of each additional extension on the image of the parent brand (e.g., John, Loken, and Joiner 1998; Milberg, Park, and McCarthy 1997) and on the future extendibility of the brand (e.g., Dacin and Smith 1994; Keller and Aaker 1992). Researchers have, for instance, studied the effect of extending a brand into a wide variety of product categories. Whereas some have argued that a broad set of extensions will create more diffuse associations and weaken the image of the parent brand (e.g., Keller and Aaker 1992; Loken and John 1993), others have argued that it will increase the range of categories suitable for future extensions (e.g., Boush and Loken 1991; Dacin and Smith 1994). Consider, for example, a brand that has extended from food blenders into dissimilar categories such as hair dryers and handheld vacuums (as opposed to similar categories such as food processors and mixers). On the one hand, the diversity of these past ex-