The mystery of manuscripts lies in being able to locate a repository holding the exact manuscript you need with information found in no other source. Manuscripts are more difficult to find and use than published books or censuses, military, or vital records available online, but their potential for unique information makes the hunt worth the effort. In this course, researchers learn to distinguish manuscripts from other records, find repositories with manuscript collections, and use finding aids to locate rare manuscripts with information relevant to solving tough research problems. Highlighted repositories and manuscripts include the Library of Congress, National Archives and Records Administration, a state archives, and a personal home archive.