The Gloucester County Library System (GCLS) is a group of individual and interdependent libraries that cooperate through a central administrative body to provide a wide range of library services for eligible patrons. Sharing resources enables members of the system to provide more cost-effective and technologically sophisticated services than any could provide operating alone.
The GCLS staff is responsible to a seven-member library commission, which is appointed by the Gloucester County Board of Chosen Freeholders. Funds for system services are provided by the member municipalities through a dedicated library tax. Of the 24 municipalities in Gloucester County, these 14 currently belong:
| Clayton | Harrison Twp. | South Harrison Twp. |
| E. Greenwich Twp. | Logan Twp. | Swedesboro |
| Elk Twp. | Mantua Twp. | Woodbury Hgts. |
| Glassboro | National Park | Woolwich Twp. |
| Greenwich Twp. | Newfield |
All residents of these communities have free access to the full services of the Gloucester County Library System through libraries located in the following towns:
| E. Greenwich Twp. | Harrison Twp. | Swedesboro |
| Glassboro | Logan Twp. | |
| Greenwich Twp. | Newfield |
Library cards are issued without charge to residents of the 14 participating communities; nonresident owners of property in a member community; not-for-profit organizations within Gloucester County; educators teaching in Gloucester County; county department heads; and those holding elected/appointed positions in county, state, or federal government.