In January 1989, the Government Reference Library opened in the County government building at 2100 Clarendon Blvd.

On April 2, 2007, the collection was moved to the new public-oriented Plaza Branch Library & Arlington Shop, located in the lobby of the County office building. The Arlington Shop was added to the space, where County merchandise is sold.

Library staff provide government reference service, manages County store and serve as "information and referral" for all County offices and services.

The Plaza Branch is not open at night and on weekends, following hours of the County government building.