More than half the children with autism in the UK are not in the sort of school their parents believe is best for them, a survey suggests.
The survey of more than 1,400 was done for the National Autistic Society, which is starting a campaign to get better education provision.
Two thirds of the parents said their choice of school had been limited by a lack of appropriate places.
Many autistic children had been bullied, the survey also found.
When families of children with autism appealed to the Special Education Needs and Disability Tribunal to get more appropriate help, 79% won their cases, the society said.
The society's campaign, under the slogan "make school make sense", aims to put pressure on national and local governments to get improvements for the estimated 90,000 children with autistic spectrum disorders.
Autism is characterised by difficulties forming relationships, problems with communication and the development of obsessional interests.
The society also wants teachers to have training in dealing with autistic children.
Its head of education, Mike Collins, said: "Autism is a complex disability that is widely misunderstood.
"Too often, children and young people with autism are placed in inappropriate schools, with teaching staff who don't have relevant training in the disability and in an environment that doesn't meet their needs."
Schools Minister Lord Adonis has been summonsed to appear before a Special Education Needs and Disability Tribunal hearing next month in the case of a boy in Hertfordshire who has a statement of special needs.
The boy's parents say he has been discriminated against because his school placement remains undecided, whereas his peers know which junior schools they will be transferring to in the autumn.