In 1967, an extension of Sterling Memorial Library was proposed to expand the library's space for collections.^[1] Though originally proposed to house the library's East Asian collection and Yale memorabilia, librarians decided instead to utilize the new space to improve access to frequently-used materials and reserve books.^[1][2] So as not to interrupt the view of the Sterling facade from the east, the library would be constructed beneath the lawn of Cross Campus, the central axis of Yale's campus. To allow for sufficient light underground, architect Edward Larrabee Barnes proposed to sink sixteen skylights into the Cross Campus lawn. When the design was made public in 1968, Yale students and faculty, including Vincent Scully, protested that the skylights would obstruct the lawn's open space, and students physically blocked early construction activities.^[2][3][4] Barnes and the university withdrew the original design and instead configured a lighting scheme with four large entrance light wells at the corners of Cross Campus.^[5][6] The new library, opened in January 1971 at a cost of $4 million, housed 300,000 volumes and remained open 24 hours a day.^[6][7]

Although the protestors' concerns were addressed in the redesign, reception of the new Cross Campus Library was generally poor. The underground location posed significant structural and architectural challenges to the facility: the sod-covered roof persistently leaked, and the light wells let in little natural light.^[2] Students described its functional aesthetic and fluorescent lighting as "antiseptic."^[8][9]

In 2004, Yale announced a major renovation of Cross Campus Library.^[10] The two-year, US$47.8 million project, led by Thomas Beeby, was completed in October 2007.^[2][11] The library was renamed Bass Library after the renovation's lead donors, Anne and Robert Bass of Texas who donated nearly $20 million toward the effort.^[12]

Yale announced plans for another renovation in 2019, reducing the collection by transferring over 100,000 volumes, including many older, rarely used, or duplicate titles, to the adjacent Sterling Memorial Library, leaving Bass Library with a collection of approximately 40,000 volumes. The seating capacity was to be expanded from 365 to 470 in order better accommodate Yale's growing student body.^[13] After student protests, a revised plan was announced with 61,000 books to be retained in Bass library and an accelerated completion timeline to have the library available to students for the fall 2019 semester.^[14]

The library has two subterranean floors totaling 60,000 square feet (5,600 m²) which can be accessed from Cross Campus or Sterling Memorial Library.^[15] The 2007 renovation by HBRA Architects, intended to harmonize the library's interiors with those of surrounding Gothic Revival buildings, refurbished the building with stone floors, steel mullions and wood-panelled shelves and interior walls.^[2][16] Kent Bloomer, a Yale School of Architecture professor, designed ornament for the Cross Campus entrances, which references Gothic elements of Sterling Memorial Library.^[17][18]

The library is noted on campus for its "weenie bins," small cubicles available for private study.^[2][19]

The library holds approximately 150,000 books, and had held 50,000 more before its renovation.^[2][20] In 2008, the Yale College Council debuted a DVD film collection to be housed in Bass for student use.^[21] The library also loans digital media equipment to library affiliates, including DSLR cameras, audio equipment, lighting kits, and Google Glass.^[22][23][24]

• Bass Library website