 A particularly influential deployment of the DALY summary measure of population health is the Burden of Disease Project. Supported by the World Health Organization, national burden of disease studies are conducted in many nations and are widely relied on to help characterize the state of ill health globally as well as within countries. Ethical concerns about DALYs and global disease studies, often discussed in the public health literature under the heading of social issues, include whether DALYs should be age-weighted or time-discounted. Because the results of global burden of disease studies can be influential in the setting of health priorities, they illustrate well the importance of the ethics of summary measures in public health practice. 