The Arc of North Central Virginia

What are Intellectual and Developmental Disabilities?

Intellectual and developmental disabilities (IDDs) manifest during the "developmental period" and are often present at birth. They uniquely affect the trajectory of the individual’s physical, intellectual, and/or emotional development.

An intellectual disability (ID) originates before the age of 18 and is characterized by significant limitations in both intellectual functioning and adaptive behavior*, which often includes many everyday social, and practical skills.

The term developmental disability (DD) broadly identifies disabilities that are attributable to a mental and/or physical impairments occurring during the developmental period (before age 22) and are likely to continue indefinitely. People with DD may need help with language, learning, mobility and personal care.

DD results in substantial functional limitations in three or more of the following areas of major life activity:
(i) self-care, (ii) receptive and expressive language, (iii) learning (iv) mobility, (v) self-direction, (vi) capacity for independent living, and (vii) economic self-sufficiency.