Causation is asymmetrical in many different ways. Causes precede effects; explanations cite causes not effects. Agents use causes to manipulate their effects; they don't use effects to manipulate their causes. Effects of a common cause are correlated; causes of a common effect are not. This book by one of the preeminent philosophers of science writing today offers the most comprehensive account available of causal asymmetries. It is a major book for philosophers of science that will also prove insightful to economists and statisticians.