Celiac disease is a chronic enteropathy caused by intolerance to gluten. The true prevalence of this condition is much greater than previously recognized, with increasing numbers of silent cases being diagnosed. Population-based studies, using serologic screening, have indicated that the prevalence of celiac disease in Caucasian populations is .5%-1%. The pattern of incidence is changing, with a greater proportion of cases diagnosed later in adulthood. The pathologic lesion is characterized by a flattened small intestinal mucosa with a lymphocytic infiltrate, crypt hyperplasia, and villous atrophy. Absorptive function may be impaired and patients can experience gastrointestinal symptoms and malabsorption leading to development of anemia, osteoporosis, or other complications. Untreated celiac disease is associated with significant morbidity and increased mortality, largely owing to the development of enteropathy-associated intestinal lymphoma. The pathologic changes and symptoms resolve when gluten is excluded from the diet for a sustained period.