For decades, management consultants and the popular business press have urged large firms to flatten their hierarchies. Flattening (or delayering) typically refers to the elimination of layers in a firm’s hierarchy and the broadening of managers’ spans of control. The alleged benefits flow primarily from pushing decisions downward to enhance market responsiveness and improve accountability and morale. Has flattening delivered on its promise? This article demonstrates that flattening management layers can have the opposite effect from their intention. In fact, flat-tened firms typically exhibit more control and decision making at the top.