The National Aeronautics and Space Administration (NASA) explores space, and researches Earth systems, the solar system, and the universe.

The National Agricultural Library (NAL) is the main source of information and research on agriculture.

The Agricultural Statistics Service (NASS) studies and provides the market with detailed information about U.S. agriculture.

The National Archives and Records Administration (NARA) preserves U.S. government records, manages the Presidential Libraries system, and publishes laws, regulations, Presidential, and other public documents.

The National Cancer Institute (NCI) conducts and supports research, training, health information distribution, and other programs related to the cause, diagnosis, prevention, and treatment of cancer, rehabilitation from cancer, and the continuing care of cancer patients and the families of cancer patients.

The National Capital Planning Commission (NCPC) crafts long-range plans and policies for the National Capital Region. The Commission provides building and zoning advice to Washington, DC and the surrounding area, and approves various federal construction plans.

The National Cemetery Administration (NCA) provides burial space for Veterans and their eligible family members, and maintains national cemeteries as national shrines, sacred to the honor and memory of those interred or memorialized there.

The National Center for Complementary and Integrative Health (NCCIH) conducts and supports research and provides information about complementary health products and practices. It is part of the National Institutes of Health.

The National Constitution Center is a state-of-the-art museum dedicated to the study of the U.S. Constitution. The museum is also a national hub for constitutional education and outreach.

The National Council on Disability (NCD) makes recommendations to the President and Congress on policies affecting Americans with disabilities. They empower individuals with disabilities and promote equal opportunity.

The National Credit Union Administration (NCUA) charters and supervises federal credit unions and insures savings in federal and most state-chartered credit unions.

The National Defense University (NDU) provides educational opportunities for military personnel and civilians.

The National Endowment for the Arts (NEA) funds, promotes, and strengthens the creative capacity of our communities by providing all Americans with opportunities for arts participation.

The National Endowment for the Humanities (NEH) funds humanities programs in the United States such as museums, archives, libraries, colleges, universities, public television, radio stations, and individual scholars.

National Flood Insurance Program (NFIP) provides affordable insurance to property owners and encourages communities to adopt and enforce floodplain management regulations.

The National Gallery of Art collects, preserves and exhibits art works, and works to promote the understanding of art through research and educational programs.

The National Geospatial-Intelligence Agency (NGA) provides location-based intelligence in support of national security.

The National Guard provides trained units to the states, territories and the District of Columbia to protect life and property. The Guard also provides trained units to defend the United States and its interests all over the globe.

The National Health Information Center (NHIC) helps connect health professionals and consumers to the organizations that can best answer their questions by providing up-to-date contact information for the most reliable resources.

The National Heart, Lung, and Blood Institute (NHLBI) provides training, and education programs to promote the prevention and treatment of heart, lung, and blood diseases to enhance the health of all individuals.

The National Highway Traffic Safety Administration (NHTSA) investigates safety defects in motor vehicles, sets and enforces fuel economy standards, helps states and local communities reduce the threat of drunk drivers, promotes the use of safety belts, child safety seats and air bags, investigates odometer fraud, establishes and enforces vehicle anti-theft regulations, conducts research on driver behavior and traffic safety, and provides consumer information on motor vehicle safety topics.

The National Indian Gaming Commission is a regulatory body that oversees some aspects of gaming on Indian lands, often complementing the work of Indian regulators.

The National Institute for Occupational Safety and Health (NIOSH) conducts research and makes recommendations for the prevention of work-related injury and illness.

The National Institute of Allergy and Infectious Diseases (NIAID) provides health information on allergic, infectious, and immunologic diseases. Diseases include food allergy, sinusitis, and genital herpes. Consumers can call or write to the institute with questions and can order publications over the phone or on the Web site.

The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) supports research into the causes, treatment, and prevention of arthritis, musculoskeletal, and skin diseases.

The National Institute of Corrections (NIC) gives training, technical assistance, and information services to federal, state, and local corrections facilities.

The National Institute of Deafness and Other Communication Disorders (NIDCD) supports biomedical and behavioral research on hearing, balance, smell, taste, voice, speech and language.

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) supports the research of diabetes, digestive diseases, kidney diseases, and more.

The National Institute of Food and Agriculture (NIFA) is a research and grant-making organization focused on agriculture.

The National Institute of Justice (NIJ) is dedicated to improving knowledge and understanding of crime and justice issues through science.

The National Institute of Mental Health (NIMH) conducts and supports research that seeks to understand, treat, and prevent mental illness.

The National Institute of Neurological Disorders and Stroke (NINDS) investigates the causes, prevention, diagnosis and treatment of neurological diseases such as cerebral palsy, Parkinson's disease, multiple sclerosis, autism, and stroke.

The National Institute of Standards and Technology (NIST) promotes U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life.

The National Institutes of Health (NIH) is the primary Federal agency for conducting and supporting medical research.

The National Interagency Fire Center (NIFC) coordinates the national mobilization of resources for wildland fire and other incidents throughout the United States.

The National Invasive Species Information Center (NISIC) was established in 2005 at the U.S. Department of Agriculture (USDA's) National Agricultural Library (NAL) to meet the information needs of users, including the National Invasive Species Council (Council or NISC).

The National Labor Relations Board (NLRB) enforces the National Labor Relations Act by investigating allegations of wrong-doing brought by workers, unions, or employers, conducting elections, and deciding and resolving cases.

The National Laboratories conduct scientific research and development in areas related to energy and technology.

The National Library of Medicine (NLM) is a leader in research in biomedical informatics and data science and the world’s largest biomedical library. NLM conducts and supports research in methods for recording, storing, retrieving, preserving, and communicating health information. It is part of the National Institutes of Health (NIH).

NOAA Fisheries, also known as the National Marine Fisheries Service, is responsible for the management, conservation, and protection of living marine resources within about 200 miles of the U.S. coast.

The National Mediation Board (NMB) facilitates the resolution of labor-management disputes in the rail and airline industries.

The National Nuclear Security Administration (NNSA) works to ensure that the nation's stockpile of nuclear weapons is safe and secure. It also works to ensure the safety of naval nuclear reactors, is the first responder in case of nuclear emergency, and works on worldwide nuclear nonproliferation issues.

The National Ocean Service (NOS) provides data, tools, and services that support coastal economies and their contribution to the national economy.

The National Oceanic and Atmospheric Administration (NOAA) works to understand and predict changes in climate, weather, oceans, and coasts. Their work supports severe weather preparedness, and international shipping.

The National Park Foundation (NPF) supports America’s national parks through conservation, preservation, education, and community engagement.

The National Park Service (NPS) cares for the more than 400 national parks in the United States. The National Park Service partners with local communities to assist in historic preservation and the creation and maintenance of recreational spaces.

The National Pesticide Information Center (NPIC) provides objective, science-based information about a wide variety of pesticide-related subjects, including pesticide products, pesticide poisonings, toxicology, and environmental chemistry.

The CDC National Prevention Information Network (NPIN) is the reference and referral service for information on HIV/AIDS, viral hepatitis, sexually transmitted diseases (STDs), and tuberculosis (TB).

The National Reconnaissance Office (NRO) is responsible for designing, building, launching, and maintaining intelligence satellites.

The National Science Foundation (NSF) supports research and education across all fields of science and technology, primarily through grants.

The National Security Agency (NSA) protects national security systems and information.

The National Security Council (NSC) advises the President on national security and foreign policy.

The National Technical Information Service (NTIS) provides businesses, universities, and the public access to government-funded scientific, engineering, technical, and business related information.

The National Telecommunications and Information Administration (NTIA) manages federal spectrum use, makes grants to develop and deploy broadband internet, conducts telecommunications research, and advises the president on telecommunications and information policy issues.

The National Transportation Safety Board (NTSB) investigates every civil aviation accident in the U.S. and significant accidents in other modes of transportation. Based on their investigative findings and special studies, the board makes recommendations aimed at preventing future accidents.

The National Weather Service provides weather, water, and climate forecasts and data.

The Natural Resources Conservation Service (NRCS) works with landowners for conservation planning and assistance to foster healthy ecosystems.

The Office of Natural Resources Revenue (ONRR) manages the revenues from energy and mineral leases for the use of public natural resources on the Outer Continental Shelf and onshore Federal and American Indian lands.

The Navy's primary mission is to defend the United States.

NOAA Fisheries, also known as the National Marine Fisheries Service, is responsible for the management, conservation, and protection of living marine resources within about 200 miles of the U.S. coast.

The Northern Border Regional Commission is a federal-state partnership for economic, and community development in northern Maine, New Hampshire, Vermont, and New York.

The U.S Northern Command (USNORTHCOM) is responsible for defending the continental United States and Alaska, and for coordinating with the defenses of Canada, Mexico, and the Bahamas.

The Office of Nuclear Energy works to improve the safety, cost, security, and efficiency of nuclear energy generation.

The Nuclear Regulatory Commission (NRC) regulates commercial nuclear power plants, and other uses of nuclear materials.

The Nuclear Waste Technical Review Board (NWTRB) provides scientific and technical oversight of the Department of Energy's program for managing and disposing of high-level nuclear waste and spent nuclear fuel.