The Bradley Foundation has been a strong supporter of the Philanthropy Roundtable. Between 1991 and 2015, Bradley documents on a 2016 Philanthropy Roundtable Grant History form that it has given the organization $4,837,500.<ref>Bradley Foundation, [Philanthropy Roundtable Grant History], ''Bradley Files'', 2016.</ref>
A background document from the [httphttps://www.exposedbycmd.org/bradley-files/ Bradley Files] provides insight into the history of the Philanthropy Roundtable and its activities,
:"The Roundtable began in the late 1970s under the auspices of the Institute for Educational affairs as an informal network of grant makers focused on promoting private, voluntary approaches to improve the lives of individual citizens in their respective communities, and, thereby, in the nation as a whole. Over time the Roundtable evolved into a nationwide network of donors supporting annually conferences and publications which became a free-standing organization with an independent board and staff. In this organizational arrangement the Roundtable aims to assist philanthropists in learning about effective giving strategies."