Margaret A. Hamburg became the 21st commissioner of food and drugs on May 18, 2009. The second woman to be nominated for this position, she is an experienced medical doctor, scientist, and public health executive. As the top official of the Food and Drug Administration (FDA), Dr. Hamburg is committed to strengthening programs and policies that enable the agency to carry out its mission to protect and promote the public health. From 2005 to 2009, Dr. Hamburg was the senior scientist at the Nuclear Threat Initiative, a foundation dedicated to reducing the threat to public safety from nuclear, chemical, and biological weapons. From 2001 to 2005, as the foundation’s vice president for biological programs, she advocated for broad reforms to confront the dangers of modern bioterrorism as well as the threats of naturally occurring infectious diseases such as pandemic flu. From 1991 to 1997, Dr. Hamburg served as commissioner of the New York City Department of Health and Mental Hygiene. In 1997, Dr. Hamburg accepted the position of Assistant Secretary for Policy and Evaluation in the U.S. Department of Health and Human Services. In 1994, she was elected to the membership in the Institute of Medicine, one of the youngest persons to be so honored. Dr. Hamburg graduated from Harvard Medical School and completed her residency in internal medicine at what is now New York–Presbyterian Hospital/Weill Cornell Medical Center. She conducted research on neuroscience at Rockefeller University, studied neuropharmacology at the National Institute of Mental Health, and later focused on AIDS research as assistant director of the National Institute of Allergy and Infectious Diseases.