Children and young people with autism are being let down after they leave school, a new report has said.
Autism affects around 20,000 people in Wales
The National Autistic Society Cymru (NAS Cymru) said only 11% made it through further education, training and into full-time employment as adults.
On Tuesday the Moving On Up? document will be discussed at the assembly's cross-party autism group, attended by Education Minister Carwyn Jones.
The Welsh Assembly Government has said it is working on an autism strategy.
Autism can affect the ability to understand and communicate, interact socially with others and to think and behave flexibly.
NAS Cymru, which spoke to teenagers and their parents for the report, has blamed a lack of support at transition stages between education and employment.
Of those who did actually receive some assistance in "transition planning", the report found 45% were dissatisfied with the process and only 26% of parents felt the support offered was adequately co-ordinated.
The charity has called for a number of measures including better career advice and more work experience.
Thomas Hughes, 17, from Caerphilly, was diagnosed with autism at the age of three and has recently finished a college course but worries his autism could hold him back.
"As soon as I get worried a lot, I'll start panicking - I get panic attacks and my heart beats faster than normal," he said.
"When I feel like that, I just want to be inside and be away from everyone until I feel better."
But he said he was hard-working, independent and polite and was very keen at the prospect of finding a job.
"I am excited because I would be getting some cash and doing it for myself and working for it - I find it very important," he added.
Liz Withers, from NAS Cymru, said many people with autism had a great deal to offer and should have access to appropriate support.
"Young people with autism can find change and anxiety over their future particularly hard to deal with and many are failing to fulfil their potential due to a lack of support at this vital stage in their lives," she said.
"It is imperative that the Welsh Assembly Government ensures that early and effective transition planning is in place for every young person with autism."
An assembly government spokesperson said it has recently consulted on a draft Autism Strategy for Wales which aims to improve the quality of life of people with autism and is now considering responses before publishing the final document.
It has also provided an extra £1.7m to local councils in a revenue settlement in recognition of the needs of children and young people with autism.