The Bureau of Indian Affairs (BIA) is the oldest bureau of the United States Department of the Interior. The BIA is responsible for the administration and management of land held in trust by the United States for American Indians, Indian tribes, and Alaska Natives.

The National Park Service cares for a large network of natural, cultural, and recreational sites across the United States. The treasures in this system, which is the first of its kind in the world, have been set aside by the American people so that they can be preserved, protected, and shared. People from all around the world visit American national parks to experience America's story, marvel at the natural wonders, and have fun.

The US Fish & Wildlife Service works with a variety of partners to conserve, protect, and enhance fish, wildlife, and plants and their habitats for the continuing benefit of the American people. Although a relative newcomer to the Department of the Interior, the Fish & Wildlife Service's programs are among the oldest in the world dedicated to the conservation of natural resources.

The Bureau of Land Management is responsible for carrying out a variety of programs for the management and conservation of resources on about 13 percent of the total land surface of the United States (more than 40 percent of all land managed by the Federal government).

Established in 1905, the Forest Service is an agency of the U.S. Department of Agriculture. The Forest Service manages public lands in national forests and grasslands across about 193 million acres of land, which is an area equivalent to the size of Texas.

The United States Army Corps of Engineers is the world's largest public engineering, design, and construction management agency. Their diverse workforce of biologists, engineers, geologists, hydrologists, natural resource managers, and other professionals meets the demands of changing times and requirements as a vital part of America's army.

The Surface Deployment and Distribution Command provides global surface deployment and distribution services (including transportation engineering and research) to meet the objectives of the United States military.

The Bureau of Reclamation constructs and maintains dams, powerplants, reservoirs, and canals in the western United States, and is the largest wholesaler of water in the country.

The Presidio Trust is an innovative federal agency created to save the Presidio. For 218 years, "The Presidio" served as a U.S. Army military fort located at the northern tip of the San Francisco Penninsula, spanning 1,500 acres within California's Golden Gate National Recreation Area. In 1996 Congress, in a demonstration of innovative thinking and bipartisan collaboration, created the Presidio Trust and transferred jurisdiction of 80 percent of the Presidio to this new federal agency (the National Park Service manages the 300 coastal acres).

The Trust was given a mandate to preserve the areas of the Presidio under its jurisdiction and attract non-federal resources to the park to ensure that it would ultimately be sustained without direct annual taxpayer support.