William G. Crook, MD, received his medical education at the University of Virginia, the Pennsylvania Hospital, Vanderbilt, and Johns Hopkins. He is an Emeritus Fellow of the American Academy of Pediatrics; the American College of Allergy, Asthma and Immunology; and the American Academy of Environmental Medicine. He is also a member of the American Medical Association, and the American Academy of Allergy and Immunology. Dr. Crook is the author of over a dozen books and numerous articles in medical and lay literature