This is an editorial opinion written by J. Michael McGinnis, MD, MPP, on findings by John Hopkins Boomberg School of Public Health connecting life expectancy with income level. It has long been known from national-level data that incomes and standards of living are associated with life expectancy, that education levels are powerful predictors of health, that behavioural factors, such as tobacco use and poor diet and activity patterns, are major contributors to early death, and that, in the aggregate, medical care is not a strong determinant of the health of populations. This study brings those observations to the community level for which the potential effect is substantial.