The AI-native agency model is emerging across three major verticals of professional services. Each represents a multi-billion dollar market where AI can fundamentally transform how services are delivered, priced, and scaled. These three pillars — sales, marketing, and back-office — represent the broadest opportunity for AI-native disruption, and they share a common thread: labor-intensive work that follows repeatable patterns, making it ripe for automation. If you are exploring how to build or invest in an AI-native agency, understanding these verticals is essential.