The Alexander Graham Bell Family Papers span the years 1834-1970, with the bulk of the material concentrated during the period 1855-1922. They include correspondence, diaries, journals, speeches, publications, and scientific notebooks of Alexander Graham Bell, his wife, Mabel Gardiner Hubbard Bell, and their forebears and descendants, members principally of the Bell, Hubbard, Grosvenor, and Symonds families. They document Bell's varied activities throughout his entire career. Although the bulk of the items pertains to the invention of the telephone in 1876, Bell's contributions to the education of the deaf and his scientific and technological interests in a wide range of subjects are also amply represented, including eugenics, marine engineering, and aviation.

Among the scientific material in the papers is a group of notebooks in which Bell recorded his daily experiments and observations, including the entry for March 10, 1876: "I then shouted into M[outhpiece] the following sentence: 'Mr. Watson - come here - I want to see you.' To my delight he came and declared that he had heard and understood what I said."

Although much of Bell's voluminous correspondence is contained in the General Correspondence series, an even larger part is included in a Subject File. Among the many people with whom Bell corresponded are Edward M. Gallaudet, Joseph Henry, Helen Keller, George Kennan, Samuel P. Langley, Guglielmo Marconi, Simon Newcomb, John Wesley Powell, Charles Sumner Tainter, and several presidents of the United States, including Ulysses S. Grant, Theodore Roosevelt, William H. Taft, and Woodrow Wilson.

The Family Papers series includes papers of Alexander Graham Bell's father, Alexander Melville Bell, a leader in the field of vocal physiology and elocution, and Mabel Gardiner Hubbard Bell's father, Gardiner Greene Hubbard, one of the founders of the telephone industry and the first president of the National Geographic Society. There is also a group of letters exchanged between Alexander Graham and Mabel Gardiner Hubbard Bell, 1875-1921. The Family Papers extend to many of Bell's descendants, including members of the Fairchild and Grosvenor families.

Additions made to the collection in 1981 and 1998 include correspondence and related papers of the Genealogical Record Office founded by Bell to study the impact of heredity on longevity. Also included are docket books of United States and British patents, published volumes of the some of which were annotated by Alexander Graham Bell, correspondence of Mabel Gardiner Hubbard Bell and her daughter, Marian Fairchild, scrapbooks, and court proceedings of Bell patent litigation.