Reform movement in Judaism is a historic and on-going religious and social movement that originated simultaneously in the early nineteenth century in the United States and Europe. The term is used by two widely read and frequently cited historians of the movement: David Philipson and Michael Meyer. Philipson wrote The Reform movement in Judaism (1903, 1931) covering the movement from its beginnings up until 1930. Meyer wrote Response to Modernity: A History of the Reform Movement in Judaism (1978). Meyer's book, the first general history of the movement since Philipson, updates Philipson's coverage to reflect modern concerns with bias and to extend the history of the movement up to the 1970s.