US real estate consumers, unlike many others across the world, have access to a near-complete inventory of existing homes for sale. This function, facilitated by MLSs nationwide, faces notable challenges heading into 2026, including market share consolidation, technology that makes marketing listings outside the MLS easier and an aggressive push by the nation’s largest brokerage to expand exclusive inventory. This chapter outlines the mechanics of the comprehensive marketplace, its vulnerabilities, what is required for its success and what this means for the industry.