Castle Square Tenants Organization | 162 followers on LinkedIn. 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.