This document lists several important U.S. organizations: Lockheed Martin, a major defense contractor; the National Air and Space Museum and Udvar-Hazy Center, which house and exhibit aviation and space artifacts and technology; the National Institutes of Health, the primary agency for biomedical and public health research; the Pentagon, the headquarters of the United States Department of Defense; and the U.S. Securities and Exchange Commission, the federal agency responsible for regulating the securities industry and enforcing federal securities laws.