Celiac disease is a permanent intolerance to ingested gluten that results in immunologically mediated inflammatory damage to the small-intestinal mucosa. Celiac disease is associated with both human leukocyte antigen (HLA) and non-HLA genes and with other immune disorders, notably juvenile diabetes and thyroid disease. The classic sprue syndrome of steatorrhea and malnutrition coupled with multiple deficiency states may be less common than more subtle and often monosymptomatic presentations of the disease. Diverse problems such as dental anomalies, short stature, osteopenic bone disease, lactose intolerance, infertility, and nonspecific abdominal pain among many others may be the only manifestations of celiac disease. The rate at which celiac disease is diagnosed depends on the level of suspicion for the disease. Although diagnosis relies on intestinal biopsy findings, serologic tests are useful as screening tools and as an adjunct to diagnosis. The treatment of celiac disease is lifelong avoidance of dietary gluten. Gluten-free diets are now readily achievable with appropriate professional instruction and community support. Both benign and malignant complications of celiac disease occur but these can often be avoided by early diagnosis and compliance with a gluten-free diet.