Australia’s National Disability Insurance Scheme (NDIS) has grown too big, too fast.

The NDIS is a government-funded program providing support to more than 760,000 disabled Australians. It launched in 2013 as a way to make disability support more accessible and equitable.

But public support for the NDIS is faltering. It’s one of the most expensive items in the federal budget, expected to cost taypaxers more than A$50 billion this year. And it’s a flawed system in urgent need of reform.

Reform is coming in May, with the federal government aiming to reduce the scheme’s annual growth from 10% to between 5% and 6% in the forthcoming budget.

So is that achievable? And what needs to change?

The NDIS was designed to replace an existing disability support system that was underfunded, fragmented and deeply inequitable.

In 2011, the Productivity Commission estimated the fully-developed scheme would cost $13.5 billion and would grow between 3% and 6% each year.

But this year its costs will grow to more than $50 billion. And growth is tracking at over 10% this year so far.

The government is now aiming to curb the annual growth of NDIS expenditure to 5% or 6%. This is not an unreasonable target. Both Medicare and aged care costs are projected to grow within this same range.

But if it’s not careful, the government risks hitting the target while missing the point. Rather than fixing the flaws in the NDIS, tightening at the margins alone may make the scheme worse for Australians with disability that need it most.

One of the clearest flaws is early childhood supports.

When the Productivity Commission first proposed the NDIS in 2011, it estimated how many adults and children would be supported by the scheme. Today, the number of adults on the NDIS is only slightly higher than that original estimate.........

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