Hospital consolidation has increased substantially over the last 5 years, with 95 hospital mergers occurring in 2014, the highest number since 2000.1 Moreover, it is predicted that as many as 20% of all US hospitals will seek a merger in the next 5 years.2 A recent analysis of competition in 306 geographic health care markets in the United States, known as hospital referral regions, found that none of the markets are considered “highly competitive,” and nearly half are “highly concentrated.”3 What are the implications of these new hospital conglomerates, especially in regions where one health system dominates the medical care of a population? This Viewpoint considers the implications of the growing trend of hospital consolidation with respect to quality, access, and price.