The collection is composed of materials that William Leary consulted in the process of writing his doctoral thesis on H. Alexander Smith, along with a manuscript of his thesis and materials related to Leary himself. The consulted materials include a small amount of Smith's correspondence and writings and a syllabus from a politics class he taught at Princeton University in 1929. Other materials pertaining to Smith include recollections of Smith written by his family members and his executive assistant; date books from the years 1918 and 1919, kept by an unidentified associate of Smith's in the Commission for Relief in Belgium and the Food Administration; printed materials from some of the World War I-era relief organizations Smith was involved with; and four photographs of Smith, including one inscribed to Leary. Some of the materials created by or related to Smith were given to Leary by members of Smith's family via his professor, Arthur S. Link.

In addition to a manuscript of his doctoral thesis, other documents in the collection pertaining to William Leary include correspondence written to him between 1976-1979, mostly but not exclusively related to his Smith biography, and publicity materials for his published book, Smith of New Jersey (1976).