Celiac disease is a gastrointestinal disorder characterized by inflammation, leading to injury to the mucosal lining of the small intestine. The inflammation occurs when gliadin, a protein found in such gluten-containing foods as wheat, rye, and barley, is ingested by genetically susceptible individuals. The mucosal damage and subsequent malabsorption of nutrients leads to various complications. Researchers estimate that more than 2 million people in the United States have celiac disease—a prevalence that is greater than was previously believed. Approximately 60,000 Americans are diagnosed annually with celiac disease. Until recently, diagnosis has been complicated by the fact that the indicators of celiac disease are nonspecific. However, because of the development of new, easy-to-administer serology tests, diagnosis has become much less complicated. After conducting a review of the literature, the authors recommend a serologic testing sequence for diagnosis of celiac disease and urge that adults and children with an assortment of symptoms be tested for this disease. Common signs and symptoms of celiac disease include anemia, arthralgia, fatigue, infertility, neuropathy, and weight loss, in addition to such gastrointestinal symptomatology as abdominal pain, anorexia, bloating, constipation, and diarrhea. The only treatment for patients with celiac disease remains a gluten-free diet.