Association founded in Chicago, 1905, to develop missionary spirit among Catholics and for the support of churches in poor localities of the United States. Among its activities are the building of churches in poor districts and the support of priests in such parishes, the education of students for missionary work, and the circulation of Catholic literature. An interesting feature of the society are the chapel cars, which enable missionaries to work at distant points along the railroad lines. "The Extension Magazine" is published monthly and has a circulation of 273,732. Tbe women's auxiliary and the "Child Apostles" are affiliated associations. The Catholic Church Extension Society of Canada publishes the "Catholic Register" weekly.