Peter Yarrow co-wrote "Puff, the Magic Dragon," and by any measure he's one of America's most beloved folk singers. With Peter, Paul & Mary in the 1960s and beyond, he was part of a group that changed the world of music. He's been active in changing the wider world as well, and he has never slowed down since the birth of Peter, Paul & Mary during the Kennedy administration. In 1969 he was one of the organizers of the antiwar March on Washington. In support of the rights of Jews in the former Soviet Union he wrote them anthem "Don't Let the Light Go Out." In 2000 he founded Operation Respect, a set of school and camp curricula designed to promote a culture of tolerance and respect. Peter's recent appeareances have emphasized music as a shared message and an antidote to mean-spiritedness and intolerance.