Stephen Tyng Mather was an American industrialist and conservationist who was the first director of the National Park Service. As president and owner of Thorkildsen-Mather Borax Company he became a millionaire. With his friend the journalist Robert Sterling Yard, Mather led a publicity campaign to promote the creation of a unified federal agency to oversee National Parks administration, which was established in 1916. In 1917, Mather was appointed to lead the NPS, the new agency created within the Department of the Interior. He served until 1929, during which time Mather created a professional civil service organization, increased the numbers of parks and national monuments, and established systematic criteria for adding new properties to the federal system.

The National Park Service (NPS) is an agency of the United States federal government, within the U.S. Department of the Interior. The service manages all national parks; most national monuments; and other natural, historical, and recreational properties, with various title designations. The United States Congress created the agency on August 25, 1916, through the National Park Service Organic Act. Its headquarters are in Washington, D.C., within the main headquarters of the Department of the Interior.