Mark Kleiman's 'Against Excess' charts a middle course between drug prohibition and legalization, arguing that neither extreme reflects the complexity of drug problems or the range of available responses. Kleiman, a policy analyst who advised governments on drug policy for decades, examines the costs and benefits of different regulatory approaches with empirical rigor and moral seriousness. He introduces the concept of 'grudging toleration,' accepting that some drug use will occur while designing policies to minimize harm rather than pursuing either futile prohibition or naively optimistic legalization. The book analyzes specific substances individually, recognizing that heroin, cocaine, marijuana, and alcohol present different risks requiring different responses. Kleiman is particularly insightful on how enforcement strategies matter as much as laws themselves: focused deterrence, treatment mandates, and swift-and-certain sanctions can accomplish more than mass incarceration or complete permissiveness. While the policy landscape has shifted since the book's publication, with marijuana legalization spreading, Kleiman's framework for thinking through costs and tradeoffs remains valuable. Readers will find neither culture-war posturing nor libertarian dogma but careful analysis of how to reduce the harm that drugs cause to users and communities alike.