In 2003, over half of all Australians with disability had a combination of two or more intellectual, psychiatric, sensory/speech, acquired brain injury (ABI) and physical/diverse disabilities (about 10% of the Australian population or 2 million people).

The average number of long-term health conditions associated with disabilities ranged from 3.5 for people with two disabilities to 6.2 for people with five disabilities. Dementia, autism, Parkinson's disease, schizophrenia, speech problems, and stroke were long-term health conditions more commonly associated with multiple disabilities.

Half of children aged under 15 years with psychiatric disability (42,300) or ABI (11,500) had three or more disabilities, followed by over one-third of children with sensory/speech (48,100) or intellectual disability (55,100). More than half of people aged 15-44 years with ABI (85,300) or intellectual disability (95,300) had three or more disabilities. Support needs of people with early onset multiple disabilities vary depending on the nature of their disabilities and their life stages. As they grow older, they may have higher support needs at an earlier age than people with single or late onset disability.

The more disabilities people had, the more likely they were to need help with 'core' daily activities of self-care, mobility and communication. Some combinations of disabilities had more marked effects on people's activity, participation in major life areas and related need for assistance.

A substantial proportion of care for people with multiple disabilities was provided by their family members and friends.

People with multiple disabilities who needed very frequent assistance with daily activities were much less likely to have their needs fully met than people with less frequent need for assistance.

School students with a mix of intellectual and other disabilities were more likely than other students with a mix of disabilities to have schooling restrictions and to rely on special support or arrangements at school.

Over half of children with psychiatric disability and two or more other disabilities had a nervous or emotional condition or mental illness causing restriction, or requiring help or supervision.

People aged 15-64 years with a mix of psychiatric and physical/diverse disabilities, and in combination with another type of disability, were more likely than others to have severe or profound employment restriction. Over one-third of people with three disabilities, and almost half of people with four or five disabilities, had profound employment restriction.

Among people with four or five disabilities, 30% were unable to go out as often as they would like, to participate in community activities; over 40% were living in institutions and a majority (77%) was aged 65 years or over.

Access to aids and equipment is critical to older people with multiple disabilities. Around 70% of people aged 65 years or over with four or five disabilities and mobility limitation, relied on mobility aids.