A hospital peer review case looks like a dispute about clinical competence and is almost never decided on that question. Federal law grants a hospital a presumption of immunity if its process met four standards, and a court reviewing the action asks whether the process was adequate rather than whether the medical judgment was right. This article explains why that structure exists, what the four standards actually require, and how the entire field reorganized itself around a reporting threshold measured in days. It covers the fair hearing that is not a trial, the bylaws that are a contract, the privilege that protects the same documents in one case and not in another, and the employment clause that lets a hospital end a career without a hearing at all. It closes with the antitrust exposure that survives immunity, the due process overlay at public hospitals, and what actually determines outcomes for a physician and for a hospital.