Public health encompasses a broad array of programs designed to prevent the occurrence of disease and injury within communities. But policy makers have little evidence to draw on when determining the value of investments in these program activities, which currently account for less than 5 percent of US health spending. We examine whether changes in spending by local public health agencies over a thirteen-year period contributed to changes in rates of community mortality from preventable causes of death, including infant mortality and deaths due to cardiovascular disease, diabetes, and cancer. We found that mortality rates fell between 1.1 percent and 6.9 percent for each 10 percent increase in local public health spending. These results suggest that increased public health investments can produce measurable improvements in health, especially in low-resource communities. However, more money by itself is unlikely to generate significant and sustainable health gains; improvements in public health practices are needed as well.