They arise from our own acts and they are imposed on us. We find risks everywhere--from genetically modified crops, medical malpractice, and stem-cell therapy to intimacy, online predators, identity theft, inflation, and robbery. Using simple conceptual frameworks from decision theory and behavioural research, they examine the science and practice of creating measures of risk, showing how scientists address risks by combining historical records, scientific theories, probability, and expert judgment. In this Very Short Introduction, Baruch Fischhoff and John Kadvany draw on the sciences and humanities to explore and explain the many kinds of risk. 2011. Risk: A Very Short Introduction describes what has been learned by cognitive scientists about how people deal with risks, applying these lessons to diverse examples, and demonstrating how understanding risk can aid choices in everyday life and public policies for health, safety, environment, finance, and many other topics.