The term or name for condition we know today as intellectual disability has changed over time; most recently the condition was primarily known as mental retardation.
AAIDD is proud to have been a leader in the adoption of the term intellectual disability in the clinical, scholarly, public policy, and education arenas.
Although the name has changed, for more than 50 years the three essential elements for all US-based definitions for this condition—limitations in intellectual functioning, behavioral limitations in adapting to environmental demands, and early age on onset—have not substantially changed.
On this website are a number of historical documents that use the term mental retardation. While the language of these documents need to be understood within their historical or legal contexts; the underlying concepts, arguments, findings, and recommendations are consistent with the vision and values of the Association.