Upwards of 100 million Americans have it. There is no diagnostic test for it. Treatment options are often inadequate, and some people pretend to have it when they don’t. Contributors to the May issue explain why each of these statements about pain is true, and explore clinical approaches that lie between the underestimation and overtreatment of pain. Three themes emerge; (1) pain is a subjective experience, influenced by physical, social, and cultural factors and, hence, immeasurable, (2) management, especially of long-term pain, is difficult, and (3) pain is costly to patients and society, so responsible pain management is urgently needed.