Learning lessons from previous pandemics is not merely an academic exercise. Our experiences from 1918 and other 20th-century pandemics helped us prepare for and respond to the 2009 H1N1 pandemic. In addition to better understanding these earlier pan-demics, we must continue to learn and apply lessons from our experience with the current H1N1 pandemic to improve our ability to respond to future pandem-ics. Any reflection on the first pandemics of the 20th and 21st centuries must begin with gratitude for the fruits of science and technology, many of which were unimaginable in 1918. We can now detect, prevent, and treat disease; clarify the dynamic circumstances of pandemics; and save lives. TODAY’S TOOLS