Perkins+Will was commissioned to provide extensive studies, planning and pre-design preparation for the rehabilitation of San Francisco’s historic City Hall. The monumental Beaux Arts building was completed in 1915, and includes one of the largest domes in the United States. The building suffered from years of deferred maintenance and incompatible alterations and was in need of an extensive structural upgrade to correct severe seismic deficiencies. The rehabilitation provided the opportunity to re-open important public spaces that had been filled in and altered, and to uncover skylights in the elegant light courts. In addition to planning, our work included earthquake damage and repair study, a damage survey of non-structural elements, and a building life-safety evaluation. We also provided an accessibility evaluation to ensure accessibility requirements met applicable codes and federal guidelines for rehabilitating historic buildings.