Celiac disease (CD) is a very common medical disorder in the general population. It results from sensitivity to a protein called gluten that is found in many grains. There presently is no cure for CD, but treatment with a gluten-free diet can effectively control or reverse symptoms in a high percentage of patients. CD is under recognized and under diagnosed in the general population and in those with developmental disabilities. Consequences of CD can include symptoms referred to as “digestive” as well as others that are behavioural, neurological or neuropsychological. Furthermore, there is evidence for an association between CD and early cognitive decline or dementia in the general population. In this short report, we briefly review what is known about CD and its consequences in the general population and in people with developmental disabilities. Unusual terms are explained briefly in the Glossary. This report was first presented in poster form at the 2007 Annual Symposium of the Research Special Interest Group.