Repositioning can be achieved by advertising or by research & development. Although consumers' perceptions are linked to the brand’s physical characteristics, they can be slightly influenced by communication. But the repositioning effect is limited; this is especially true when the brand awareness level is high, because a brand with which consumers are extremely familiar is more difficult to reposition. Beyond a certain level, brand repositioning can no longer be done by advertising alone. At this point one must complete an R&D project with physical characteristics matching consumers' needs, and then to upgrade the brand. R&D projects will take at least one period to complete, while repositioning through advertising has an immediate effect.