The book presents a major meta-analysis of 'value of a statistical life' (VSL) estimates derived from surveys where people around the world have been asked about their willingness to pay for small reduction in mortality risks. The analysis seeks to explain the differences in the estimates, for example across countries. Differences in incomes and the magintude of the risk reduction people have been asked to value were found to be the factors having the strongest impact on VSL, but a number of other policy-relevant factors are also important. Based on the meta-analysis, and a broad review of the literature, the book also presents clear advice on how VSL values best can be used in assessments of environmental, health and transport policies, such as in cost-benefit analyses. Using explicit VSL estimates to quantify the benefits to society of fatality risk reductions can play an important role in the development of more cost-effective public policies.