Butler Library houses 2 million volumes which comprise the University's collections in the humanities, with particular strengths in history (including government documents and social science materials published before 1974), literature, philosophy and religion, as well as one of the country's most extensive collections of materials pertinent to the study of Greco-Roman antiquity. The stacks consist of 12 floors of books and the entrance is at the third floor Circulation Desk.

Butler Library is the largest of the more than twenty libraries and collections comprising Columbia University Libraries. The building was financed by Standard Oil executive and philanthropist Edward S. Harkness and designed by James Gamble Rogers, opening in 1934 as "South Hall." It was renamed in 1946 in honor of Nicholas Murray Butler, president of the University from 1902-1945.

Although traditional in its Italian Renaissance design, the building was equipped with the latest library technology available at the time. The core of the library is the fifteen-tier steel-shelved stack, which was then the largest stack ever built as a single unit. The stacks (though not the reading rooms and offices) were air-conditioned; stack lighting was designed by George Ainsworth to approach the quality of natural light; there was an electric book lift, an electric book conveyor, and a lighted call board behind the main desk to inform student researchers that books were ready to be checked out.

• Circulation Department
  854-2235; 854-3537
  Check out books located in the stacks at the third floor Circulation Desk. If your book is not on the shelf, the circulation staff can help you determine if the item is already checked out. They can also place a hold or recall on the item, or search for a missing book.
  
• Reference Department
  301 Butler Library, 854-2241
  The reference collection houses the main card catalog for CUL (including a separate serials catalog). While subject bibliographies constitute the backbone of the collection, other notable strengths are an impressive number of current directories, guides, handbooks, a wide range of language dictionaries, periodical indexes from all over the world, and a particularly strong collection of biographical dictionaries. The reference collection also boasts many new CD-ROM products which provide computer access to several periodical indexes, abstracts, and large reference works.
• Card Catalogs
  310 Butler
  These catalogs are the central catalogs for the Columbia University Libraries. They indicate the location of most materials cataloged before 1986 in departmental libraries as well as in the stacks. There are eight CLIO Plus terminals for public use in the reference area, and an additional 12 CLIO terminals opposite the Butler Circulation Desk.
  
• Periodicals and Microforms Reading Room (PMRR)
  401 Butler Library, 854-4704
  The Periodicals Collection contains unbound issues of approximately 2,000 periodicals, covering the fields of classics; literature, language and linguistics; history; philosophy; and religion. It includes some journals of a more general and popular nature as well. Issues are arranged alphabetically by title on shelves in the Reading Room. Periodicals are for room use only, and a photocopier is available.
      The Microforms Collection supports the collections of the Humanities and History Division, and houses approximately half of the libraries' microform collection. It maintains a current collection of newspapers, academic journals, popular magazines, doctoral dissertations, masters' essays, indexes, bibliographies, government publications, monographs and monographic series. The Microforms Collection does not circulate, but material may be photocopied or scanned on the reader printers.