Catharine Killien, AIA/AIAS 2011 COTE Scholar In order to dramatically reduce energy consumption and curb carbon emissions in the United States, building retrofits must not only be more extensive, but also must occur on a broader scale. The numerous challenges involved in doing deep green retrofits has led to a relative lack of widespread success thus far in achieving retrofits on a broad scale. To examine the capacity for larger scale sustainability initiative programs to achieve retrofits on a deeper and broader scale, five case studies were developed on different programs, each operating at different scales and each aimed at improving energy efficiency in existing buildings. The programs investigated in this report are Living City Block, the Seattle 2030 District, Portland Sustainability EcoDistricts, the Chicago Climate Action Plan, and the U.S. DOE Commercial Buildings Partnership Program. These particular programs were chosen in order to achieve diversity in terms of geographical location, scale, organizational structure, and methods.