The wing of the building that currently houses Guildhall Library was opened in 1974. The original suffered immensely during the bombings of World War II. Despite the fact that the buildings nearly burned to the ground, a lot of the collection survived and was restored. Most of the materials in the collection focus on the history of London. Guildhall also houses a number of special collections such as London Stock Exchange historic records and company annual reports from 1880-1964.
Guildhall is staffed by approximately 43 employees plus volunteers. Most of the collection is closed, with only about 5% of materials out on the open shelves. The staff receive usually about 10-15 email inquiries daily from researchers and curious patrons. The staff will give up to 20 minutes of research time free of charge to patrons via email. Anything that involves more in depth research will be charged 50 pounds sterling per hour of research. They sometimes call in free lance researchers to handle jobs like these when the staff is otherwise engaged in other projects. All patrons who come into the library looking for material must fill out a request slip. Staff will usually fill the requested order in about 15 minutes. The library has three separate reading rooms in the building: one that houses books, one that houses manuscripts, and one that houses prints. Included with the prints are maps, photographs, watercolors, drawings, and other ephemera. They also have exhibits on display that readers can learn from as they do research. The Clockmakers Museum is located in the same building as Guildhall Library. Patrons can wander in and see John Harrison's famous clock on display.