Intellectual Disability is the currently preferred term for the condition historically referred to as Mental Retardation. Three decades ago, the American Association on Mental Retardation (AAMR; now known as the American Association on Intellectual and Developmental Disabilities or AAIDD) proposed a definition of Mental Retardation that emphasized intelligence but also considered two other important factors – adaptive behavior and the time of occurrence of the disabling condition: “Mental Retardation refers to significantly subaverage general intellectual functioning existing concurrently with deficits in adaptive behavior and manifested during the developmental period” (Grossman, 1983, p. 1).