This book examines the remarkable decline of mortality in Europe which began in the nineteenth century and continued in an uninterrupted fashion, into the early twentieth century. The transition of mortality between 1870 and 1920 had profound effects for European and American societies. Interpretations explaining such changes have become a hotbed of controversy. Some scholars stress the importance of improved nutrition, levels of income, and living standards as the crucial factors. Others consider public health, social organization, and scientific advances to be more significant. This volume brings to light the different positions held on these various issues, describes advances made in the field, and indicates directions for future research.