This issue of Gastroenterology Clinics of North America focuses on an important area in gastroenterology for both clinicians and researchers: neurogastroenterology and gastrointestinal (GI) motility disorders. GI motility and functional GI disorders are common reasons for patients to see physicians. Knowledge of GI motility disorders, including the evaluation and treatment of these disorders, is important for gastroenterologists, clinicians, and health care providers to appropriately care for these frequently seen patients in clinical practice. Gastrointestinal motility can be defined as motor activity in the digestive tract that mixes ingested food with digestive juices and moves luminal contents of the gastrointestinal tract in an aboral direction from the mouth toward the anus. A.