Celiac disease (CD) is a distinct disease caused by gluten from wheat and other related prolamins from rye and barley. CD is chronic, may affect multiple organs, and has autoimmune components. The clinical presentation may be diverse, reaching from frank mal-absorption to effects such as iron deficiency, anemia, or osteoporosis. The main autoantigen in CD is transglutaminase 2 (TG2), and IgA anti-TG2 antibodies have a high diagnostic accuracy. New guidelines for the diagnosis of CD in children and adolescents have recently been published. CD may be diagnosed at any age and in most populations CD is common, affecting approximately 1% of the general population. The cornerstone treatment of CD is a gluten-free diet. The diet may be cumbersome, and in children as well as adults diet adherence may present a considerable challenge. Maximal levels for gluten content in gluten-free foods are given in Codex Alimentarius. Governmental support for patients and families is important, and education and participation in a celiac patient organization is of value.