The Gloucester County Library System (GCLS) was conceived and developed in the early 1970s and approved by referendum in 1976.  In January of 1977, the Gloucester County Board of Chosen Freeholders appointed the first library commission.  The Commission quickly established book collections in libraries in member communities, municipal buildings, banks, Laundromats, gas stations, and other sites frequented by the public.  Four months later, the library system began operations with a staff of two in a storefront on Route 45 in Mantua Township.  In December of 1977, the library moved to a rented building on Woodbury-Glassboro Road in Mantua Township and functioned there until August 1982.

Between August 1982 and November 1983, the book collection that had been located in Mantua Township was placed in storage, and the staff concentrated on outreach programs to libraries in member communities.  From December 1983 until September 1994, the library was located in an 8,000 square foot building in Sewell.  The current 28,000 square foot facility, which opened in October 1994 in Mullica Hill, is nearly four times as large as the old Sewell location.  This library houses 83,350 items, and its three public meeting rooms serve numerous community organizations.

In January of 1995, the Gloucester County Library System began its role as a center for automation with the establishment of GLO-NET.  In 1998, it was designated as a regional Technology Hub by the New Jersey State Library. In 2004, GCLS libraries joined other public and academic libraries in Gloucester County in a new automation consortium, LOGIN.

The Logan Township Branch began in 1979 in a gas station on Center Square Road. Shortly thereafter the library moved to a vacant office in the Beckett Shopping Center. In 1980, the Logan Branch moved to a refurbished office trailer parked on a lot owned by the Beckett Assembly of God. Although this was meant to be a temporary situation, many years passed before the dream of a new library was realized. The new Logan Township Branch Library, a 9,660 square foot building at 101 Beckett Road, opened in October 1995 and houses 23,855 items.  The library specializes as a popular materials center and young children's door to learning in its effort to serve the growing population of this area.

The Glassboro Branch was started by the Glassboro Women's Club in 1956 with a $2,000 donation from borough funds. Since then the library has moved three times, the last time in 1979.  The library occupies 8,500 square feet of a building it shares with the Boys and Girls Club.  In 1996, the Glassboro Public Library became a branch of the Gloucester County Library System. The library houses 40,500 books, videos, CDs and other items. Children's programs, Internet access, and a public meeting room make the Glassboro Branch a thriving community center.

The Greenwich Township Branch started in a school building in 1963, thanks to the efforts of a group of interested citizens who began planning for a library in 1958.  The library was moved to a converted municipal garage for ten years, and moved to its present location in Nehaunsey School in 1975.  In January of 1999, the Gibbstown Public Library became the Greenwich Township Branch of the Gloucester County Library System.  This library houses 17,769 items and serves the surrounding community as a children's door to learning and a popular materials center.

The Swedesboro Public Library is one of the oldest public libraries in New Jersey, first established in 1783. The library was originally housed in Borough Hall and was incorporated in 1937. In 2005, it became a branch of the Gloucester County Library System.

The Gloucester County Library System now provides quality library service to residents of 14 of Gloucester County's 24 municipalities. Over 84,000 residents may take advantage of library services offered through libraries in East Greenwich, Glassboro, Greenwich (Gibbstown), Logan, Harrison Township, Newfield, and Swedesboro. More than 70 GCLS staff members, along with association library employees in libraries throughout the system, work to provide circulating and reference collections, and Homebound service as well as comprehensive children's and reference services, including public Internet access. The library's Internet web site offers the public access to library service 24 hours a day. These are just some of the many services available to all members.