More than half of all Americans are living with chronic or recurring pain, with broad numbers saying it interferes with their activities, mood and enjoyment of life — sparking a vast search for relief, from medication to bed rest, yoga or the palliative power of prayer. An exclusive survey by ABC News, USA Today and the Stanford University Medical Center finds that, excluding minor annoyances, just under half of adults have experienced pain in the last two weeks, and nearly four in 10 do so on a regular basis.

Sixty percent of all Americans have rated their last experience with pain as moderate or worse, and for twenty percent, which is approximately 40 million individuals — it was severe. Nineteen percent suffer chronic pain, meaning ongoing pain that's lasted three months or more. An additional 34 percent report recurrent pain; the rest say their usual pain experience is acute, or short-term.

This national survey paints an extensive portrait of pain in America, measuring not just prevalence and severity but also where it hurts (back and knee pain are most common), whom it effects (pain is much more frequent among older adults), and its source, impact and treatment. The survey supports a weeklong reporting project by ABC News and USA Today, "The Fight Against Pain."