The Neo-Brandeisians and Chicago School have employed different statistics to show respectively that markets are both concentrated and not concentrated, leaving Americans in the dark about who really holds corporate power. The evidence only looks contradictory due to the failure of American antitrust scholarship and regulation to understand how conglomerates collect market power across many neighboring markets, through what Paul Friederiszick calls “adjacent market takeovers.” This strategy can make firms more efficient, but it can also raise prices and weaken competition even as each individual market still looks competitive, he writes, drawing on his new paper, “The Conglomerate Power Puzzle.”