This Working Group, Histories of Scientific Observation, met several times during the years 2005-2008. The outcome of this work, a book edited by Lorraine Daston and Elizabeth Lunbeck, has been published by the University of Chicago Press in 2011. The book features engaging episodes drawn from a wide variety of sciences, ranging from meteorology, medicine, and natural history to economics, astronomy, and psychology. The contributions spotlight how observers have scrutinized everything—from seaweed to X-ray radiation, household budgets to the emotions—with ingenuity, curiosity, and perseverance verging on obsession. This book makes a compelling case for the significance of the long, surprising, and epistemologically significant history of scientific observation, a history full of innovations that have enlarged the possibilities of perception, judgment, and reason.