The common standards are not just for public schools. With all but four states having adopted them since 2010, districts have little choice but to implement the Common Core State Standards. But many private schools are also making the transition. Many Roman Catholic, Lutheran, and other private schools have adopted at least portions of the standards, in part for practical reasons. A number of leaders in private education emphasized that they adopted the common standards only after careful study and see them as worthy guideposts. Another issue for some leaders in private education is staying competitive with public schools.