In the courts and in the academy, the ostensible commitment of American tort law to individualized justice has experienced a sustained revival in recent years. Neither the modern mass tort case-law nor the scholarly literature, however, has adequately grappled with longstanding practices of de facto aggregation that have sprung up in the shadow of American tort law since the very beginnings of tort as a field. Reviewing more than a century of private aggregation from employers\u27 liability to automobile accident litigation to the modern asbestos cases, this Article contends that American tort practice has been characterized almost from the start by decentralized and private institutions for the aggregate resolution of what may be described...