Amazon’s advertising business, now the fastest growing in the world, had humble beginnings. Initially skeptical about the value of ads, Jeff Bezos and his team took tentative steps into this arena starting in 2006. Early efforts were clumsy; Amazon even outsourced some ad placements to Google and Yahoo. The company faced internal resistance, with worries that advertising could detract from the shopping experience. However, as Bezos recognized the profitability potential—advertising margins can exceed 40%—the company shifted its focus, paving the way for substantial growth. By 2024, Amazon's ad revenue reached an impressive $56 billion, dwarfing competitors like NBCUniversal, which reported only $2.6 billion. Early advertisers such as Fidelity and Ford had to convince Amazon to accept their ad dollars, and there were significant hurdles to overcome, including internal conflicts between product and ad teams. The launch of search ads, which came later, proved to be a turning point. Amazon's initial reluctance to adopt a model similar to Google’s stemmed from a desire to maintain customer-centric practices. Eventually, pressure from brands led to the creation of Sponsored Listings, which quickly gained traction. Despite these successes, Amazon's ad infrastructure was chaotic, with different teams managing separate systems and technologies. This fragmentation hindered efficiency and integration. The company eventually launched Project Barnum to streamline operations and improve the user experience for advertisers. This initiative reflects Amazon's ongoing efforts to refine its ad business as it continues to challenge and reshape the digital advertising landscape.