We explore the deep resonance between Buddhist practice and nonviolent action (in the tradition of Mohandas Gandhi, Dr. Martin Luther King, Jr., Dorothy Day, Cesar Chavez, and others). We first examine the core of Buddhist practice as expressed in the Buddha's statement: "I teach dukkha and the end of dukkha; we explicate dukkha as "reactivity." We then show how the nonviolence of Dr. King follows the same core understanding of developing non-reactive and nonviolent responses--for him especially to the institutionalized reactivity of greed and hatred. We identify six basic themes of such nonviolent action, which, in the words of John Lewis, is ultimately "love in action."