What is an intellectual disability?

Intellectual disability is a term used when a person has certain limitations both in intellectual functioning (reasoning, learning, problem solving) and in adaptive behavior, which covers a range of everyday social and practical skills.

These can present opportunities and challenges for a person to learn and develop differently than others. Individuals with an intellectual disability may take longer to learn to speak, and take care of their personal needs such as dressing or eating. A person with an intellectual disability may even require some level of support for their entire life. Intellectual disabilities are frequently grouped under the umbrella term "developmental disabilities."

There are more than 200 known causes of intellectual disability. Some common examples of intellectual disability are:

  • Down Syndrome - A genetic disorder which occurs when someone is born with a full, or partial, extra copy of chromosome 21 in their DNA. 
  • Fragile X Syndrome - A genetic condition caused by a mutation (a change in the DNA structure) in the X chromosome.
  • Fetal Alcohol Spectrum Disorder (FASD) - This refers to a number of conditions that are caused when an unborn fetus is exposed to alcohol.

In the past you had very few options if you or a family member were determined to have an intellectual disability. You could send the child to an institution or keep the child at home. In the past, it was common to send the child to an institution for life.

Today, in Ontario, children and adults with intellectual disabilities are included in our communities. They attend local schools and day cares, get jobs and pay taxes. Many people live in their own home. They may receive support from their families, friends and community-based agencies.

There are community agencies that support people with an intellectual disability at every stage of their life, including children, youth, adults and seniors. Community agencies provide essential services so people with intellectual disabilities can go to school, work and do activities.

To find a community agency near you, contact your local community information centre or go to Services Near Me for a list of services in your area.

For More Information

  • Ability Online - A moderated online community for young people with disabilities.
  • Community Living Ontario - A provincial association that promotes citizenship, belonging, and equality of people who have an intellectual disability. The website has contact information and links to Community Living centres across Ontario.
  • ConnectAbility - An interactive website with information for those working with people with intellectual disabilities. The library section has information in many languages.
  • Programs, Services and Supports - This website has links to information about the Ontario government's financial, employment, residential and family support programs.
  • Special Needs Resources - A list of supports, programs and services for families who have children or adults with special needs. From Special Needs & Moving On.

Produced in partnership with Community Living Toronto. First Published in 2009. 

Last updated: July 14, 2023 4001294