The Stockholm Library, opened in 1928, was designed by the notable Swedish architect Erik Gunnar Asplund. From its beginning, the library was an important element of the city's architecture as well as its social infrastructure. Nowadays the library asks for a change, following the new society and its challenges. The project proposes an extension, respecting the monumentality of the existing structure, complimenting it and reinforcing its relation with the surrounding. The new structure should address the lack of scale and program diversity, offering a unique infrastructure where contemporary society would provide their needs and strengthen their relationships.