From time to time, it is useful to stand back from the weekly reports of crises around the world and ask how the human race is really doing. Kenny, a World Bank economist, does this magnificently in this well-written book. Its main message is simple: that quality of life has improved greatly almost everywhere over the past century, even in places (such as Africa) where per capita incomes have stayed relatively flat. Looking at improvements in that measure, which is favored by economists, is in fact a poor way to gauge improvements in overall living conditions. Infant and maternal mortality have plummeted, and people today enjoy better nutrition and protection against disease, more education, better access to infrastructure, and greater personal freedom than ever before. To be sure, there is much room for improvement. But making progress need not be vastly expensive, since it mainly involves transmitting ideas and information. Kenny offers a lighthearted critical survey of what economists have had to say about the determinants of economic growth, but he argues that growth, although important and desirable, should not be the main objective.