National Institutes of Health
Intellectual and Developmental Disabilities Definitions
·         Intellectual disability refers to a group of disorders characterized by a limited mental capacity and difficulty with adaptive behaviors such as managing money, schedules and routines, or social interactions. Intellectual disability originates before the age of 18 and may result from physical causes, such as autism or cerebral palsy, or from nonphysical causes, such as lack of stimulation and adult responsiveness.·         Developmental disability is a severe, long term disability that can affect cognitive ability, physical functioning, or both.  These disabilities appear before age 22 and are likely to be life-long. The term “developmental disability” encompasses intellectual disability but also includes physical disabilities. Some developmental disabilities may be solely physical, such as blindness from birth. Others involve both physical and intellectual disabilities stemming from genetic or other causes, such as Down syndrome and fetal alcohol syndrome.

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California defines children with special needs as having one of the following: • Children with identified disability, health, or mental health conditions requiring early intervention, special education services, or other specialized services and supports; or • Children without identified conditions, but requiring specialized services, supports, or monitoring.

California Department of Developmental Services is the agency through which the State of California provides services and supports to individuals withdevelopmental disabilities.