Our Mission Castle Square Tenants Organization's mission is to promote the economic, educational and social empowerment of low and moderate income individuals by providing access to safe, quality affordable housing and supportive direct service programs. Accomplishments In December 2012, Castle Square Tenants Organization (in partnership with Winn Companies) completed the nation’s largest Deep Energy Retrofit on an existing affordable housing community. A Deep Energy Retrofit is defined as a renovation with energy savings greater than 50 percent, The Castle Square Apartments managed to achieve a 72 percent reduction in energy usage. The U.S. Green Building Council (USGBC) awarded CSTO with the LEED Platinum Certification, which is its highest green building rating. In 2014, Castle Square was recognized by the U.S. Environmental Protection Agency with an award for Superior Energy Performance. Buildings that earn EPA's Energy Star use 35 percent less energy and generate 35 percent fewer greenhouse gas emissions than similar buildings across the nation. CSTO also created a LEED Platinum Community Center, complete with a technology room, media room, teen space, gym, and classrooms for our elementary education programs. Since the beginning CSTO’s board, comprised of 100% residents, has demonstrated an overwhelming commitment to obtaining a better life for themselves and their community. Awards CSTO is honored to have been the recipient of the following awards over the years: 2016: Best of the Best Landscape Award, Winn Companies 2015: Community Service Award, Boston Police Neighborhood Watch Unit 2014: Energy Star, Environmental Protection Agency 2013: Social Justice Award, Chinese Progressive Association 2012: LEED Platinum, US Green Building Council Arthur F. Howe Community Service Award, The Ellis South End Neighborhood Association Vanguard Award, National Affordable Housing Management Association Mayor's Green Residential Award, City of Boston