Retail media networks are an exciting opportunity for advertisers to reach consumers at their zero moment of truth, when they are researching or about to make a purchase. The dynamics shaping the media ecosystem include audience fragmentation, ad avoidance technology, and the difficulty of maintaining a consistent brand message across multiple channels. Retail media networks offer on-site and off-site advertising opportunities, with retailers realizing significant margins from their media sales. The challenge lies in measuring the impact of in-store retail media and delivering personalized messaging to consumers. The future of retail media may involve personalized experiences through digital shelf labels or mobile devices.