It is the sixteenth largest public library system in the United States by holding and the seventh by number of visitors.

[2] In 1852, several prominent citizens established the "Brooklyn Athenaeum and Reading Room" for the instruction of young men.

It was as was the practice in those times, a private, subscription library for members, who were recruited and encouraged by the rising mercantile and business class of young men, to continue by constant reading whatever formal education they had received through a university, college, high school/private academy, or trade school.

Its collections focused on the liberal arts and the humanities such as biography, economics, history, literature, philosophy, and other applications later labeled social studies.

[4] The first main branch ("central library") moved among various buildings, including a former mansion at 26 Brevoort Place.

[11] Located at Flatbush Avenue and Eastern Parkway on Grand Army Plaza near the Prospect Heights, Crown Heights, Flatbush, and Park Slope neighborhoods, Brooklyn Public Library's Central Library contains over a million cataloged books, magazines, and multimedia materials.

[13] The Shelby White and Leon Levy Information Commons opened at Central Library on January 15, 2013.

It features an open workspace with 25 computers and seating and outlets for more than 70 laptop users; 7 meeting rooms, including one that doubles as a recording studio; and a 36-seat training lab.

[15][16] Every Brooklyn Public Library branch is equipped with a "New Americans Corner" that provides information on immigration, citizenship and other materials.

[23] Linda E. Johnson was named president and CEO on August 16, 2011, after having served as the institution's interim executive director since July 1, 2010.

Mack-Harvin was the first African American woman to lead a major public library system in New York state.