The cooperation movement (c. 1900-1930) was the first in a series of twentieth century attempts to broaden responsibility for language instruction by involving faculty across the curriculum, the most recent of which is the current writing-across-the-curriculum movement. Cooperation in language instruction was another of the widespread urban educational reforms of the Progressive Era (c. 1900-1920). Cooperation was fundamentally a response to the new structural and curricular differentiation of modern secondary and higher education, which in turn reflected the specialization of knowledge and work in urban industrial society. Its theory shaped by organicist social thought, its practice by scientific management, the movement influenced writing instruction not only in comprehensive secondary schools and universities, but also in vocational, technical, and professional schools, in settlement houses, and in adult extension classes (particularly those for immigrants). Though the cooperation movement finally had little effect on writing instruction in the 1930s and beyond, it raised central issues of curricular organization and language pedagogy to which later reformers returned.