Writing across the curriculum (WAC) is a movement within contemporary composition studies that concerns itself with writing in classes beyond composition, literature, and other English courses. According to a comprehensive survey performed in 2006–2007, approximately half of American institutes of higher learning have something that can be identified as a WAC program.[1] In 2010, Thaiss and Porter defined WAC as "a program or initiative used to 'assist teachers across disciplines in using student writing as an instructional tool in their teaching'".[1] WAC, then, is a programmatic effort to introduce multiple instructional uses of writing beyond assessment.[2] WAC has also been part of the student-centered pedagogies movement (student-centered learning) seeking to replace teaching via one-way transmission of knowledge from teacher to student with more interactive strategies that enable students to interact with and participate in creating knowledge in the classroom.[3] This page principally concerns itself with WAC in American colleges and universities. WAC has also been important in Britain, but primarily at the K–12 level.