Brand extension success factorsProblem definition and objectivesIn a highly competitive environment, organizations are convinced that launching new products in order to stratify consumer needs can lead to a increasing the success of a company. The new product launch strategy can be successful but comes with some risks. In fact, 30 to 35 percent of new product launches fail. Due to some factors, such as high advertising costs and increasing competition, it becomes increasingly difficult to introduce new products onto the market. An increasingly popular strategy to reduce these risks is to pursue a brand extension. In fact, this strategy has grown since 1984. In the United States, through 1984, the share of additional products in total new product introductions in the fast-moving consumer goods segment was only 40% (Aaker & Keller 1990, p. 27), the share amounted to 90% in 1991 (Rangaswamy & Burke & Oliva 1993). During the two decades, more than 40 studies have been conducted around the world to determine the conditions that determine the success of a brand extension, but some aspects are unknown or unexplored. In this work, our goal is to determine exactly what the factors of a successful brand extension are and how these factors are valued in relation to consumer perception. To maximize our chances of efficiency, we will first focus on theory and then ask different segments of the population to answer a questionnaire about a brand we have chosen previously: Virgin. Say we will apply our theoretical approach to two brands, one that failed and another that was completely successful. The questionnaire will help you understand the impact of consumer behavior and expectations in a typical brand extension situation. So we have to describe a problem like: What are the factors that the Virgin group uses to successfully conduct its brand extension strategy? In other words, in which sectors has Virgin succeeded or failed in terms of its extension strategy? Theoretical basisDescription of the concept of brand extensionFirst, we will base our approach on a theoretical basis to explain the basis of our work and our questionnaire.Brand extension is a marketing strategy that uses the same brand for different products, for products of different categories or of the same category. It is a risky strategy that must aim to increase sales or brand value.