During the term of the first president of the United States, George Washington (None; Federalist, 1789-1797), the first ten amendments to the Constitution were ratified by the States on Dec. 15, 1791 and have become enshrined as the "Bill of Rights." Subsequently, there has been a steady progression of laws enacted, executive orders signed and court rulings issued, designed to protect the health of human and animal populations and the ecosystems upon which they depend for survival, beginning with the term of office of America's second president, John Adams (1797-1801). With rare exceptions, such progress in protections of public health and/or the environment within the USA continued unabated, under Federalist, Democratic-Republican, Whig, National Union, Republican and Democrat party presidencies. Shortly after January 20, 2017, consequent to the inauguration of President Donald John Trump, the nation's 45th President, the trend toward dismantling many of these protections for environmental health and environmental sustainability appears to be dramatically accelerating. Accordingly, it may be useful to review the timeline for such legislation, court rulings, key appointments and executive orders, in order to both place the contemporary de-regulations within their historical context and to inform the strategy, going forward, for advocacy on behalf of protecting both public health and environmental sustainability. A chronological summary of such legislation, regulations, executive orders, appointments & pertinent court rulings, during the terms of office of America's presidents, follows: