Over the past ten years, methodological development to measure disease burden, new data sets for large populations (eg. Tanzania, South Africa) and research to critically evaluate existing data sets (eg. China) have greatly increased the potential to measure disease burden more reliable in all regions of the world. Yet, to date, this research does not exist in one consolidated form. There is neither a comprehensive presentation of new methods, data sets and their evaluation, nor is there a single compilation of the enormous amount of epidemiological detail by age, sex, cause, sequelae and region of the deaths and DALYs for the year 2000. This publication of the results of the Global Burden of Disease 2001 Study, and the CRA Study, by detailed age, sex, cause, region and risk factor will provide a unique description, in one volume, of the entire global epidemiology of diseases, injuries, and risk factors at the turn of the 21st century. This will be an invaluable resource for global and regional health policy for decades to come.