Markets sometimes fail. But so do regulatory efforts to correct market failures. Sometimes regulations reach too far, condemning good activities as well as bad, and sometimes they don't reach far enough, allowing bad behavior to persist. In this highly instructive book, Thomas A. Lambert explains the pitfalls of both extremes while offering readers a manual of effective regulation, showing how the best regulation maximizes social welfare and minimizes social costs. Working like a physician, Lambert demonstrates how regulators should diagnose the underlying disease and identify its symptoms, potential remedies, and side effects before selecting the regulation that offers the greatest net benefit. This book should be read by policymakers, students, and anyone else interested in understanding how the best regulations are crafted and why they work.