Advertising is a profit-oriented mass communication technique aimed at conveying a message in order to stimulate demand for a product. It must be distinguished from propaganda, public relations and sales promotion. It is a strategy, a plan of action. It aims to incite consumers to increase their propensity to buy dedicated products. While empirical analyses on advertising are abundant, proper economic studies are rare, often partial, even biased. There is no real economic theory of advertising, but rather sociological and philosophical reflections. Advertising creates the desire to buy, not only to satisfy a need satisfied by the purchase, but also to communicate socially by highlighting a social status., La publicité est une technique de communication de masse à but lucratif visant à transmettre un message afin de stimuler la demande d'un produit. Elle doit être distinguée de la propagande, des relations publiques, de la promotion des ventes. C'est une stratégie, un plan d'action, Elle vise à inciter les consommateurs à accroître leur propension à acheter les produits dédiés. Si les analyses empiriques sur la publicité sont abondantes, les études proprement économiques sont plus rares, souvent partielles, voire partiales. Il n'existe pas vraiment de théorie économique de la publicité, mais plutôt des réflexions sociologiques et philosophiques. La publicité crée le désir d'acheter, non plus seulement pour satisfaire un besoin satisfait par l'achat, mais aussi pour communiquer socialement en mettant en évidence un statut social. Advertising is a profit-oriented mass communication technique aimed at conveying a message in order to stimulate demand for a product. It must be distinguished from propaganda, public relations and sales promotion. It is a strategy, a plan of action. It aims to incite consumers to increase their propensity to buy dedicated products. While empirical analyses on advertising are abundant, proper economic studies are rare, often partial, even biased. There is no real economic theory of advertising, but rather sociological and philosophical reflections. Advertising creates the desire to buy, not only to satisfy a need satisfied by the purchase, but also to communicate socially by highlighting a social status.