What is the difference between NDIS and NDIA? The National Disability Insurance Scheme is known as NDIS. It is basically the legislation that was passed by the government to set up the Scheme to support people with a disability. The National Disability Agency is known as NDIA. It is the government organisation which makes the NDIS happen. NDIA employs a range of staff to support people with a disability and their families to plan for their life and provides the funding to support this to happen.