Catholics remained outside the Scottish educational system until 1918. The Church preferred mixed-sex infant schools and either single-sex schools or separate departments. In small towns and rural areas the schools were mixed-sex. Women were considered naturally best suited to teach infants and girls, but even in boys' schools, female assistants were increasingly employed in the later Victorian period. Female religious orders were crucial for developing Catholic education in larger urban centres, but by 1918 only 4% of Scotland's Catholic schoolteachers were members of religious orders. Lay women quickly became numerically predominant in elementary education and were key to implementing the Church's strategy to enhance the respectability of a largely immigrant community through separate schools. It is the contention here that the part played by lay women in Catholic schooling needs to be considered to reflect more widely on the place of women in Scottish education. (Contains 110 footnotes.)