Intellectual and developmental disabilities

What it is

Intellectual disability means a person has limits in how they learn and think.
It can also make some daily skills harder.
It starts when a person is young.
It lasts for life.
Many people with intellectual disability also have strengths.
Sources: CDC, Mencap, and AAIDD.

The short sections at the top of this page use easy-read language. The full chapter below has more detail.

Common experiences

Each person is different.
Some children sit up, walk, or talk later than other children.
Some people find it hard to remember things.
Some find it hard to solve problems.
Some find social rules hard to understand.
Many people have strengths too.
Sources: CDC and AAIDD.

What helps

Short sentences and simple words help.
Pictures help too.
Help people make their own choices.
This is called supported decision-making.
Support that fits the person can help them do more over time.
Sources: Inclusion Europe, Supported Decision-Making, and AAIDD.

Across life

Some people need a little support.
Some people need a lot of support.
Many things can cause intellectual disability.
Examples are Down syndrome, fragile X syndrome, and fetal alcohol syndrome.
Often nobody knows the cause.
Sources: Mencap, ICD-11, and CDC.

Evaluation and treatment

A health professional can check how a person learns and thinks.
They also check everyday skills.
Examples are looking after yourself and using money.
Children can get help early.
In the United States, families can contact the local early intervention agency for children under 3.
For children 3 and older, they can contact the public school.
Sources: NICHD, APA, and CDC.

Myth vs fact

Myth: People with intellectual disability cannot make their own choices.
Fact: With the right help, people can make choices about their own lives.
This is called supported decision-making.
Sources: Supported Decision-Making and the UN Convention on the Rights of Persons with Disabilities.

Myth: Intellectual disability and dyslexia are the same.
Fact: They are different.
Mencap says dyslexia is a learning difficulty because it does not affect intellect.

Full chapter

Definitions and terminology

Intellectual disability is a term used when there are limits to a person's ability to learn at an expected level and to function in daily life (CDC fact sheet). It is the term used in United States federal law and by the American Association on Intellectual and Developmental Disabilities, or AAIDD. The American Psychiatric Association's DSM-5 fact sheet gives the diagnostic name as intellectual disability (intellectual developmental disorder), and the ICD-11 uses the name disorders of intellectual development (APA fact sheet; ICD-11). In the United Kingdom, the usual term is learning disability. The NHS says a learning disability affects the way a person learns new things throughout their life, and Mencap describes dyslexia as a learning difficulty because, unlike a learning disability, it does not affect intellect (NHS; Mencap). In United States education law, specific learning disability is a separate category from intellectual disability, so the same words can mean different things in different countries (34 C.F.R. 300.8). Federal law used the term mental retardation until Rosa's Law (Public Law 111-256), signed on October 5, 2010, replaced it with intellectual disability. The law states that the change was made without any intent to change coverage, eligibility, rights, responsibilities, or definitions (Rosa's Law). NICHD says IDD is the term often used when intellectual disability and other disabilities are present (NICHD condition information). People may prefer different words for themselves, so it is respectful to ask.

How the AAIDD defines it

The AAIDD defines intellectual disability as a condition characterized by significant limitations in both intellectual functioning and adaptive behavior that originates before the age of 22. Intellectual functioning, also called intelligence, refers to general mental capacity, such as learning, reasoning, and problem solving. The AAIDD says an IQ test score of around 70 or as high as 75 indicates a significant limitation in intellectual functioning. Adaptive behavior is the collection of conceptual, social, and practical skills that are learned and performed by people in their everyday lives, and standardized tests can also determine limitations in adaptive behavior (AAIDD). The AAIDD explains the age 22 limit by saying that important brain development continues into our 20s (AAIDD FAQ). Sources differ on the age limit for onset. NICHD says intellectual disability starts any time before a child turns 18, and the AAIDD says before 22 (NICHD fact sheet; AAIDD).

How the DSM-5-TR and ICD-11 describe it

The DSM-5-TR uses a similar structure: deficits in intellectual functioning, deficits in adaptive functioning, and onset during the developmental period. The American Psychiatric Association's DSM-5 fact sheet describes the conceptual domain as language, reading, writing, math, reasoning, knowledge, and memory; the social domain as empathy, social judgment, interpersonal communication skills, and the ability to make and retain friendships; and the practical domain as self-management in areas such as personal care, job responsibilities, money management, recreation, and organizing school and work tasks. It says the DSM-5 emphasizes using both clinical assessment and standardized testing of intelligence, that intellectual disability is considered to be approximately two standard deviations or more below the population, which equals an IQ score of about 70 or below, and that severity is based on adaptive functioning rather than IQ scores alone (APA fact sheet). The ICD-11 describes the mild level as significantly below average intellectual functioning and adaptive behaviour approximately two to three standard deviations below the mean (about the 0.1st to 2.3rd percentile), and the severe level as approximately four or more standard deviations below the mean, in both cases based on appropriately normed, individually administered standardized tests. It says severe and profound levels are separated only by adaptive behaviour, because existing intelligence tests cannot reliably or validly distinguish among people with intellectual functioning below the 0.003rd percentile (ICD-11).

Developmental disabilities as a wider group

Developmental disabilities are a group of conditions due to an impairment in physical, learning, language, or behavior areas. They begin during the child's developmental period, may affect day-to-day functioning, and usually last throughout a person's lifetime (CDC). The CDC lists ADHD, autism spectrum disorder, cerebral palsy, hearing loss, fragile X syndrome, and Tourette syndrome as examples. NICHD describes developmental disabilities as a broader category of often lifelong challenges that can be intellectual, physical, or both (NICHD condition information), and the AAIDD says intellectual disability is one of several conditions known collectively as developmental disabilities (AAIDD). In United States federal law, a developmental disability is a severe, chronic disability attributable to a mental or physical impairment or a combination of both, manifested before age 22, likely to continue indefinitely, and resulting in substantial functional limitations in three or more of seven areas: self-care, receptive and expressive language, learning, mobility, self-direction, capacity for independent living, and economic self-sufficiency. The same law lets a child from birth to age 9 with a substantial developmental delay, or with a specific congenital or acquired condition, be considered to have a developmental disability if the child would likely meet the criteria later without services (42 U.S.C. 15002). Because these definitions differ, a person can have a developmental disability without having an intellectual disability. Several other guides on this site cover conditions the CDC counts as developmental disabilities, including the Autism, ADHD, and Tourette syndrome and tics guides.

How common it is

Estimates depend on how intellectual disability is defined and counted. The CDC says about 1 in 6 children in the United States aged 3 to 17 have one or more developmental disabilities, which is a much wider group than intellectual disability (CDC). For intellectual disability itself, NICHD says current estimates suggest that 2 to 3 percent of children in the United States have some form of it (NICHD fact sheet). A National Academies report says estimates for children in the United States from epidemiologic studies range widely, from 8.7 to 36.8 per 1,000. It reports that in the National Health Interview Survey the rate stayed between 6.7 and 7.5 per 1,000 across four periods from 1997 to 2008, and that in the 2011 to 2012 National Survey of Children's Health, 1.1 percent of children aged 2 to 17 currently had the condition. It adds that serious intellectual disability (an IQ below 50 with deficits in adaptive behavior) is consistently found at 2.5 to 5 per 1,000 children, that mild intellectual disability ranges from as low as 2 to more than 30 per 1,000, and that the risk of mild intellectual disability is highest among children of low socioeconomic status (NASEM, 2015). The wide range reflects how studies define and count intellectual disability, and mild intellectual disability varies the most.

What causes it

The CDC lists Down syndrome, fetal alcohol syndrome, fragile X syndrome, genetic conditions, birth defects, and infections as common known causes that act before birth. Other causes happen during or after birth, such as serious head injury, stroke, or certain infections. For many children, the cause of the intellectual disability is not known (CDC fact sheet). NICHD lists genetic mutations, additions, or deletions (for example, Rett syndrome is caused by changes in the MECP2 gene); chromosome abnormalities such as an extra or missing chromosome (Down syndrome results from an extra copy of chromosome 21); exposure to certain substances in the womb (alcohol can lead to fetal alcohol spectrum disorder); infections during pregnancy (infants whose mothers had cytomegalovirus during pregnancy may have hearing, vision, and neurological problems); problems during childbirth (such as umbilical cord problems that restrict oxygen to the brain); and traumatic brain injury and preterm birth (NICHD causes). The NHS adds that the mother becoming ill in pregnancy, genetic changes sometimes passed on from a parent, illness such as meningitis or injury in early childhood, and certain health problems such as spina bifida may be causes, and that we do not always know why a person has a learning disability (NHS). The CDC says most developmental disabilities are thought to be caused by a complex mix of factors, including genetics, parental health and behaviors during pregnancy, complications during birth, infections, and exposure to environmental toxins such as lead (CDC). Because the cause is so often unknown, support is planned around what the person needs and not around the cause.

Conditions that can come with intellectual disability

The NHS says everyone with Down's syndrome has some level of learning disability, and so do many people with cerebral palsy. It also says some people with epilepsy have a learning disability, and so do many autistic people (NHS). The CDC counts fragile X syndrome and cerebral palsy among the developmental disabilities, along with autism, ADHD, and Tourette syndrome (CDC), and it lists Down syndrome, fetal alcohol syndrome, and fragile X syndrome among the common known causes of intellectual disability (CDC fact sheet). NICHD names Rett syndrome and fetal alcohol spectrum disorder as examples of conditions with genetic or prenatal causes (NICHD causes). Many people with intellectual disability do not have any of these conditions, because for many children no cause is found (CDC fact sheet). When a person has more than one condition, each one can need its own support. The Autism guide on this site covers autism in depth.

Strengths, learning, and growth

The AAIDD says limitations often coexist with strengths, and that an individual's level of life functioning will improve if appropriate, personalized supports are provided over a sustained period (AAIDD). Mencap says that although a learning disability is permanent, many people can develop new skills throughout their lives, and that with the right support and an inclusive community, people with a learning disability can thrive (Mencap). The CDC says that to help a child reach their full potential, it is very important to get help as early as possible (CDC fact sheet). Strengths and interests differ from person to person, so the best way to find out what someone is good at and enjoys is to ask them and to watch what they choose when they have a choice.

Early signs and early help

The CDC says children with intellectual disability may sit up, crawl, or walk later than other children; learn to talk later, or have trouble speaking; find it hard to remember things; have trouble understanding social rules; have trouble seeing the results of their actions; and have trouble solving problems (CDC fact sheet). These signs are reasons to ask for an assessment. They do not on their own show that a child has an intellectual disability. The CDC recommends talking with the child's doctor or nurse, possibly seeing a developmental pediatrician or other specialist, and contacting the local early intervention agency for children under 3 or the public school for children 3 and older. NICHD says newborn screening and prenatal tests such as amniocentesis or chorionic villus sampling may identify specific conditions (NICHD fact sheet). The CDC stresses that getting help as early as possible is very important.

Getting evaluated

NICHD says diagnosis typically involves a test of intelligence or cognition, often assessed by the range of scores on an IQ test, and that health care providers also observe behavior and assess adaptive functioning (NICHD fact sheet). The DSM-5 fact sheet says both clinical assessment and standardized testing of intelligence should be used (APA fact sheet). The ICD-11 refers to appropriately normed, individually administered standardized tests, or comparable behavioural indicators when standardized testing is unavailable (ICD-11). The AAIDD describes an IQ score of around 70 or as high as 75 as indicating a significant limitation, and says standardized tests can also determine limitations in adaptive behavior (AAIDD). In United States schools, eligibility in the intellectual disability category uses this definition: significantly subaverage general intellectual functioning, existing concurrently with deficits in adaptive behavior and manifested during the developmental period, that adversely affects a child's educational performance (34 C.F.R. 300.8). The CDC advises families to talk with the child's doctor or nurse and to contact the local early intervention agency (for children under 3) or the public school (for children 3 and older) (CDC fact sheet). Adults who were never assessed can ask a doctor about a referral to a psychologist. The results are a guide to the support a person may need. The AAIDD says that personalized supports given over a sustained period improve a person's level of life functioning (AAIDD).

Support needs, not just a number

The DSM-5 fact sheet says severity is based on adaptive functioning rather than IQ scores alone (APA fact sheet). The ICD-11 separates the severe and profound levels only by adaptive behaviour, because intelligence tests cannot reliably do so at that level (ICD-11). The AAIDD says limitations often coexist with strengths and that appropriate, personalized supports improve functioning over time (AAIDD). Taken together, this points to planning around the person: what the person wants, what the person finds hard, and what help makes it possible. A plan can ask what help the person wants with learning and understanding, with relationships and social situations, and with daily living such as personal care, money, and work tasks, which are the skill areas the DSM-5 fact sheet describes (APA fact sheet). Needs can change over time, so supports should be reviewed. Mencap says that many people can develop new skills throughout their lives (Mencap).

Education and the move to adult life

In the United States, the Individuals with Disabilities Education Act names intellectual disability as one of its disability categories (34 C.F.R. 300.8). The CDC advises contacting the local early intervention agency for children under 3 and the public school for children 3 and older (CDC fact sheet). When a student has an individualized education program (IEP), the IEP must include transition services. These begin not later than the first IEP to be in effect when the child turns 16, or younger if the IEP team decides it is appropriate. The IEP must include appropriate measurable postsecondary goals based on age-appropriate transition assessments related to training, education, employment, and, where appropriate, independent living skills, and it must list the transition services, including courses of study, needed to help the child reach those goals (34 C.F.R. 300.320). Families and students can ask what the goals are and how progress will be measured. Education rules differ in other countries and in Canadian provinces. The Resources page includes general rights information.

Communication and access

Inclusion Europe's standards for easy-to-read information say to use easy-to-understand words that people will know well, to explain difficult words clearly if you must use them, to use the same word for the same thing throughout, and to avoid difficult ideas such as metaphors. They say to keep sentences short and to use positive and active sentences where possible. They note that percentages and big numbers are hard to understand, and they advise a clear font at least the size of Arial 14, text aligned to the left, a new sentence on a new line, and images next to text to show what it is about. The standards also say to always involve people with intellectual disabilities when making information, including in checking how easy it is to understand (Inclusion Europe). For people who communicate without speech or with limited speech, ASHA describes augmentative and alternative communication (AAC) as an area of clinical practice that addresses the needs of individuals with significant and complex communication disorders, and it lists intellectual disability among the conditions in which people may benefit. ASHA states that AAC does not affect motivation to use natural speech and can help improve natural speech when therapy addresses both, that there are no prerequisites for AAC intervention, and that research suggests impaired cognition does not preclude communication (ASHA). The short sections at the top of this page follow the easy-read rules, and the Toolkit page has communication cards that show a phrase in large text.

Health and mental health

NHS England says people with a learning disability often have poorer physical and mental health than other people, and that an annual health check can improve people's health by spotting problems earlier. In England, anyone over the age of 14 with a learning disability can have an annual health check. NHS England also says people with a learning disability can sometimes find it hard to know when they are unwell, or to tell someone about it (NHS England). Diagnostic overshadowing is a bias in which symptoms of a psychological disorder are falsely attributed to a known diagnosis of intellectual disability. Reiss and colleagues coined the term in 1982 for the situation in which a diagnosis of intellectual disability is so salient that it 'overshadows' other psychological disorders (Dell'Armo & Tassé). For families, carers, and clinicians, this means that a new change in mood, sleep, eating, or behavior is worth looking into, and should not be put down to the disability without checking. The NHS links learning disability with Down's syndrome, cerebral palsy, epilepsy, and autism, so health care for a person with a learning disability may need to cover several conditions at once (NHS). If you are in crisis or thinking about suicide, the Crisis help page lists where to turn.

Rights and legal capacity

Article 12 of the United Nations Convention on the Rights of Persons with Disabilities says countries shall recognize that persons with disabilities enjoy legal capacity on an equal basis with others in all aspects of life, and shall take appropriate measures to provide access to the support they may require in exercising their legal capacity. It says safeguards must respect the rights, will and preferences of the person, be free of conflict of interest and undue influence, be proportional and tailored to the person's circumstances, apply for the shortest time possible, and be subject to regular review by a competent, independent and impartial authority or judicial body (UN CRPD).

Supported decision-making and capacity laws

Supported decision-making allows individuals with disabilities to make choices about their own lives with support from a team of people they choose. It is an alternative to guardianship: instead of a guardian making a decision for the person, the person makes their own decisions, and supporters, who can be family members, co-workers, friends, and past or present providers, help by providing information and assistance (Supported Decision-Making). In England and Wales, the Mental Capacity Act 2005 sets out principles: a person must be assumed to have capacity unless it is established that they lack it; a person is not to be treated as unable to make a decision unless all practicable steps to help them have been taken without success; a person is not to be treated as unable to make a decision merely because they make an unwise decision; any act or decision made for a person who lacks capacity must be in their best interests; and regard must be had to whether the purpose can be achieved in a way that is less restrictive of the person's rights and freedom of action (Mental Capacity Act 2005). Laws on guardianship and decision-making differ by country, state, and province, so ask a local disability rights organization or legal aid service about the rules where you live.

Home, community, and work

Article 19 of the Convention recognizes the equal right of all persons with disabilities to live in the community, with choices equal to others. It says people should have the opportunity to choose their place of residence and where and with whom they live on an equal basis with others, and should not be obliged to live in a particular living arrangement. It also says people should have access to a range of in-home, residential, and other community support services, including personal assistance necessary to support living and inclusion in the community, and to prevent isolation or segregation from the community (UN CRPD). In the United States, the Supreme Court held in Olmstead v. L.C. (1999) that 'unjustified isolation, we hold, is properly regarded as discrimination based on disability.' The Court said states are required to provide community-based treatment for people with mental disabilities when the state's treatment professionals determine that such placement is appropriate, the affected people do not oppose such treatment, and the placement can be reasonably accommodated, taking into account the resources available to the state and the needs of others with mental disabilities (Olmstead v. L.C.). For work, the Job Accommodation Network (JAN) lists accommodation ideas for people with intellectual disability. For executive functioning and memory these include checklists, calendars and planners, reminders, color coded systems, written instructions, visual schedulers, recorded directives, additional training time, a support person, and job coaches. For reading they include modified written materials, a qualified reader, and screen reading or text reader software (JAN). The Resources page lists JAN and general rights information.

Self-advocacy and identity

Self-Advocates becoming Empowered (SABE) describes its mission as people with lived experience coming together to advocate and educate about the issues that are important to them, and it uses the slogan 'Nothing About Us Without Us' (SABE). Inclusion Europe's standards say to always involve people with intellectual disabilities when making their information (Inclusion Europe), and Article 12 of the Convention says people enjoy legal capacity on an equal basis with others in all aspects of life (UN CRPD). Mencap says that with the right support and an inclusive community, people with a learning disability can thrive (Mencap), and the AAIDD says limitations often coexist with strengths (AAIDD). Identity is personal. Some people use the words intellectual disability or learning disability for themselves, and some prefer other words or do not use a label at all. SABE is one example of a group where people with lived experience speak for themselves. The Resources page lists The Arc and other organizations.

For families, teachers, and colleagues

Speak to the person, not about them, and give them time to answer. Use short sentences and words the person knows, explain any difficult word, and check understanding in a respectful way (Inclusion Europe). Offer pictures, written steps, and reminders. JAN lists written instructions, checklists, visual schedulers, and job coaches as workplace accommodations (JAN). Let the person make choices, and help them understand the options instead of deciding for them (Supported Decision-Making). Do not assume that a person cannot communicate because they do not speak. ASHA states that there are no prerequisites for AAC intervention and that impaired cognition does not preclude communication (ASHA). Take new changes in mood, sleep, eating, or behavior seriously and look for a cause, because symptoms can be wrongly put down to the disability (Dell'Armo & Tassé; NHS England). Ask what the person wants to achieve, and start planning for adult life early: in the United States, transition planning must begin by age 16 in an IEP (34 C.F.R. 300.320). Families and carers can also look for support for themselves, and the NHS notes that charities and other resources offer help to families and carers (NHS).

Sources

1. American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.).
2. Centers for Disease Control and Prevention. Facts About Intellectual Disability. https://www.cdc.gov/disability-and-health/media/pdfs/2024/12/IntellectualDisability.pdf (retrieved October 4, 2026).
3. American Psychiatric Association. DSM-5 fact sheet: Intellectual Disability. https://www.psychiatry.org/File%20Library/Psychiatrists/Practice/DSM/APA_DSM-5-Intellectual-Disability.pdf (retrieved October 5, 2026). This fact sheet describes the DSM-5 (2013), not the DSM-5-TR.
4. World Health Organization. International Classification of Diseases, 11th Revision (ICD-11), 6A00 Disorders of intellectual development: entries 6A00.0 (mild) and 6A00.2 (severe), as reproduced at https://www.findacode.com/icd-11/code-1207960454.html and https://www.findacode.com/icd-11/code-1508286189.html (retrieved October 5, 2026).
5. National Health Service (UK). Learning disabilities. https://www.nhs.uk/conditions/learning-disabilities/ (retrieved October 5, 2026).
6. Mencap. What is a learning disability? https://www.mencap.org.uk/learning-disability-explained/what-learning-disability (retrieved October 5, 2026).
7. Individuals with Disabilities Education Act regulations, 34 C.F.R. 300.8 (child with a disability). https://www.law.cornell.edu/cfr/text/34/300.8 (retrieved October 5, 2026).
8. Rosa's Law, Public Law 111-256 (S. 2781, 111th Congress), signed October 5, 2010. https://www.congress.gov/bill/111th-congress/senate-bill/2781 (retrieved October 5, 2026).
9. Eunice Kennedy Shriver National Institute of Child Health and Human Development. Intellectual and developmental disabilities (IDDs): condition information. https://www.nichd.nih.gov/health/topics/idds/conditioninfo (retrieved October 5, 2026).
10. American Association on Intellectual and Developmental Disabilities. Defining criteria for intellectual disability. https://www.aaidd.org/intellectual-disability/definition (retrieved October 4, 2026).
11. American Association on Intellectual and Developmental Disabilities. Frequently asked questions about the 12th edition of Intellectual Disability: Definition, Diagnosis, Classification, and Systems of Supports. https://www.aaidd.org/docs/default-source/intellectualdisability/12th-ed-twenty-questions-faq.pdf (retrieved October 4, 2026).
12. Eunice Kennedy Shriver National Institute of Child Health and Human Development. Intellectual and developmental disabilities (IDDs): fact sheet. https://www.nichd.nih.gov/health/topics/factsheets/idds (retrieved October 5, 2026).
13. Centers for Disease Control and Prevention. Developmental disability basics. https://www.cdc.gov/child-development/about/developmental-disability-basics.html (retrieved October 4, 2026).
14. Developmental Disabilities Assistance and Bill of Rights Act, 42 U.S.C. 15002 (definitions). https://www.law.cornell.edu/uscode/text/42/15002 (retrieved October 5, 2026).
15. Boat, T. F., & Wu, J. T. (Eds.). (2015). Mental disorders and disabilities among low-income children, Chapter 15, Prevalence of intellectual disabilities. National Academies Press. https://www.nationalacademies.org/read/21780/chapter/20 (retrieved October 5, 2026).
16. Eunice Kennedy Shriver National Institute of Child Health and Human Development. What causes intellectual and developmental disabilities (IDDs)? https://www.nichd.nih.gov/health/topics/idds/conditioninfo/causes (retrieved October 4, 2026).
17. Individuals with Disabilities Education Act regulations, 34 C.F.R. 300.320 (definition of individualized education program). https://www.law.cornell.edu/cfr/text/34/300.320 (retrieved October 5, 2026).
18. Inclusion Europe. Information for all: European standards for making information easy to read and understand. https://www.inclusion-europe.eu/easy-to-read-standards-guidelines/ and https://inclusion-europe.eu/wp-content/uploads/2015/03/2113-Information-for-all-16.pdf (retrieved October 5, 2026).
19. American Speech-Language-Hearing Association. Augmentative and alternative communication (Practice Portal). https://www.asha.org/practice-portal/professional-issues/augmentative-and-alternative-communication/ (retrieved October 5, 2026).
20. NHS England. Learning disability annual health checks. https://www.england.nhs.uk/learning-disabilities/improving-health/annual-health-checks/ (retrieved October 5, 2026).
21. Dell'Armo, K., & Tassé, M. J. Diagnostic overshadowing of psychological disorders in people with intellectual disability: A systematic review. American Journal on Intellectual and Developmental Disabilities (pre-press version). https://www.aaidd.org/docs/default-source/prepressarticles/diagnostic-overshadowing-of-psychological-disorders-in-people-with-intellectual-disability-systematic-review.pdf (retrieved October 5, 2026).
22. United Nations. Convention on the Rights of Persons with Disabilities, Article 12 (https://social.desa.un.org/issues/disability/crpd/article-12-equal-recognition-before-the-law) and Article 19 (https://social.desa.un.org/issues/disability/crpd/article-19-living-independently-and-being-included-in-the-community) (retrieved October 5, 2026).
23. Supported decision-making resource site. About supported decision-making. https://supporteddecisions.org/about-supported-decision-making/ (retrieved October 5, 2026).
24. Mental Capacity Act 2005 (England and Wales), section 1, the principles. https://www.legislation.gov.uk/ukpga/2005/9/section/1 (retrieved October 5, 2026).
25. Olmstead v. L.C., 527 U.S. 581 (1999), decided June 22, 1999. https://tile.loc.gov/storage-services/service/ll/usrep/usrep527/usrep527581/usrep527581.pdf (retrieved October 5, 2026).
26. Job Accommodation Network. Intellectual disability. https://askjan.org/disabilities/Intellectual-Disability.cfm (retrieved October 5, 2026).
27. Self-Advocates becoming Empowered (SABE). https://sabeusa.com/ (retrieved October 5, 2026).

Citations are listed so you can verify claims and read further. Guidance is revised over time, so check for newer editions.