This paper proposes an integrative model of the effect of brand extension on brand image. The four key processes of the model are 1) the formation of initial brand image toward parent brand, 2) the perception of fit, 3) the formation of attitude toward brand extension and 4) the effect of brand extension attitude on parent brand image. Moderator and control variables of these processes are identified and classified into four groups: 1) consumer characteristics, 2) extension marketing support factors 3) parent brand characteristics and 4) extension characteristics. This integrative model leads to the identification of missing links and variables in past research, resulting in a propositional inventory for future studies. The paper ends with a reflection on the long-term perspectives of scientific inquiry on brand extensions. Key words: Brand extensions, brand associations, brand image, extension attitudes.