The number of Australian children diagnosed with Autism Spectrum Disorder may have skyrocketed but many will be "un-diagnosed" in adulthood.
Early diagnosis and programs are helping those with Asperger syndrome - now known as high functioning autism - deal with social deficits and other challenges.
"We are now getting people who become what we technically call sub-clinical," autism guru Dr Tony Attwood told AAP.
This means they've reached a "level of expression" that doesn't need specialist services or support.