Federally qualified health centers play a major role in providing health care to the underserved, and will remain an important part of the health care safety net even under reforms that will increase the number of Americans with health insurance. We show that the investments made in federally qualified health centers during 1996-2006 clearly translated into an increase in services available to patients, including mental health and substance abuse treatment and counseling and staffing. One particularly notable finding is that an additional $500,000 in federal grants translates into 540 more uninsured patients treated.