The American Civil Liberties Union litigates on behalf of civil liberties, including religious liberties. It is based in Washington, D.C., and has many chapters throughout the United States. Anthony D. Romero is its executive director.

The Thomas More Law Center is a law firm dedicated to the defense and promotion of the religious freedom of Christians. Contact president and chief counsel Richard Thompson in Ann Arbor, Mich.

The Southeastern Legal Foundation is a legal advocacy group based in Marietta, Ga., and Washington, D.C. Its lawyers have argued in support of prayer in public places and for the public display of the Ten Commandments. Contact Todd Young.

The Rutherford Institute is an international, nonprofit civil liberties organization based in Charlottesville, Va. It represents clients in religious liberty issues. Contact media liaison Nisha N. Whitehead.

The Pacific Justice Institute is a nonprofit legal defense organization that specializes in religious and civil liberties cases. Its president is Brad Dacus. The institute is based in Sacramento, Calif.

The Liberty Counsel is a nonprofit litigation and educational organization based in Orlando. It is dedicated to advancing religious liberty, “the sanctity of human life and the traditional family.” Mathew Staver is its founder and chairman.

The Christian Law Association defines itself as a “ministry of legal helps” to “Bible-believing churches” and Christians who are experiencing legal difficulty in practicing their religious faith because of governmental regulation, intrusion or prohibition. It is based in Seminole, Fla., and headed by David Gibbs Jr.

Rothgerber Johnson and Lyons is a for-profit law firm whose specialties include religious issues, including religious liberty and church-state issues. It has offices in Denver and Colorado Springs in Colorado and in Casper, Wyo. Its website includes a religious liberty archive with court cases and many relevant documents. Contact Patrice Hettinger.

The North American Religious Liberty Association advocates a “broad interpretation” of the Free Exercise Clause and supports religious freedom. It is based in Simi Valley, Calif. Alvin Kibble is its president.