A new, 10,000 SF library, the Mark Twain branch fulfills a severe need for community and educational services in south Los Angeles. The building is characterized by a tilted, deeply curved clerestory roof, which creates a dramatic interior space and provides natural lighting for library patrons. The primary structural system for the building is a combination of steel framing and masonry shear walls, with extensive use of rolled tubular sections to create the clerestory.