William Chey, MD, is professor of internal medicine and professor of nutrition at the University of Michigan, where he leads the Functional Gastrointestinal Disorders Research Group. His research interests include diagnosis and treatment of irritable bowel syndrome, constipation, fecal incontinence, gastroesophageal reflux disease, and H. pylori infection. During his 30 years of treating people with constipation, Dr. Chey has written more than 300 manuscripts, reviews, and book chapters. He received his medical degree from Emory University and completed a fellowship in gastroenterology at the University of Michigan.