In the United States, just one government-sponsored funding program focuses on the health effects of low doses of ionizing radiation. That is the Energy Department's Low-Dose Program, which supports biomedical radiation research at academic institutions throughout the United States. In the most recent presidential budget for fiscal 2012, funding for this program is slated to decrease from $25 million to $14 million. Is this reasonable? Do scientists and policymakers already know enough about the health risks of low doses of ionizing radiation to make quality decisions?