The Establishment Clause of the First Amendment prevents the government from establishing or directly aiding religion. Over the past thirty years, the opinion of the Supreme Court has shifted from a policy of strict separation between church and state to a position of neutrality. Under this policy, one religion is not favored over another and no distinction is made between religious and non-religious groups in secular issues involving aid unspecific to religious worship. This move toward neutrality has directly affected the eligibility of historic active religious places to receive federal funding for historic preservation and conservation. The Supreme Court has ruled that the religious activity of an institution cannot be assumed to be inextricably tied to its secular activity; that connection must be proved. While this reasoning lends itself to educational challenges, it leaves many questions for historic preservation grants, in which it is more difficult to discern the religious from the secular. Can a building be separated from its use? What if the use is divided between the religious and the secular? The site management of these historic religious properties shows a growing trend toward the professionalizing of secular non-profit organizations to navigate these questions and provide a clear public benefit.