Paul A. Offit, M.D., is Chief of the Division of Infectious Diseases and Director of the Vaccine Education Center at the Children's Hospital of Philadelphia, as well as the Maurice R. Hilleman Professor of Vaccinology and Professor of Pediatrics at the University of Pennsylvania School of Medicine. An expert in the field of vaccines, he is a recipient of many awards, including the J. Edmund Bradley Prize for Excellence in Pediatrics from the University of Maryland Medical School; the Young Investigator Award in Vaccine Development from the Infectious Disease Society of America; and a Research Career Development Award from the National Institutes of Health. Visit his website at www.paul-offit.com.