The materials collections at the OWHL are entirely supported by Endowed Funds. The library holds more than 90,000 physical books, organized by the Dewey Decimal System. The print collection is particularly strong in history and social sciences, English literature, science, and the arts. Because of our membership in the North Of Boston Library Exchange (NOBLE), our users may borrow materials (more than three million items) from any of the member libraries. Requested books will be delivered to the OWHL within a few days.