By Alison Smith
BBC News education reporter
Dyslexia can cause a range of reading and learning problems
More teachers will be trained to identify and support children in England with dyslexia, as a report says greater expertise is needed in schools.
Government adviser Sir Jim Rose, who recently reviewed the English primary school curriculum, said parents also needed guidance on the help available.
Children's Secretary Ed Balls has announced £10m for extra help, including training for 4,000 teachers.
Charity Dyslexia Action called it a "landmark report".
"I have met many parents who have struggled to get the right support for their children," said Mr Balls, launching the report on Monday with Sir Jim at Lyndhurst School in Southwark, south London.
"Sir Jim's recommendations mean that every child's reading needs will be monitored, those who need extra help will receive one to one support, and children with severe literacy difficulties will have the help of a specialist dyslexia teacher.
"We are going to say loud and clear today, through Jim Rose's report, that dyslexia exists, it is a condition where there should be help for every child in every school.
"We are going to make sure that every teacher gets some basic training to recognise the issues."
Training for 4,000 teachers means that there will be at least one specialist teacher for each local group of schools, he said.
The report also says the government should commission online training courses for teachers to help them find the right techniques for teaching literacy.
And it says there should be clearer guidance for parents about what help is available for dyslexia.
In his report, Sir Jim defines dyslexia as a "learning difficulty which primarily affects skills involved in accurate and fluent word-reading and spelling".
The charity Dyslexia Action said it was a "great step forward" to have a definition of dyslexia which those affected could recognise and accept.
Sir Jim says dyslexia should not be treated as a distinct category of people, but as a continuum, much like other disorders.
He adds that children with dyslexia need to be taught in a highly-structured way, with a strong emphasis on the phonic structure of language.
Those with dyslexia can experience mild or more severe difficulties, according to dyslexia organisations.
However, some educational experts question how helpful it is to define dyslexia in such broad terms.
Professor Julian Elliott, head of education at Durham University, questioned how dyslexia differed from children who simply found reading difficult.
He said: "Most definitions - including I suspect the one in this report - simply describe children who have difficulty learning to read and write.
"We've known for generations there are plenty of such kids in society.
"They do need special help - but what they don't need is some pseudo-medical label. It's just really woolly thinking."
Dyslexia Action's chief executive, Shirley Cramer, said reading difficulties were a classic symptom of dyslexia, but that other difficulties were often also involved, and some could occur together.
She described dyslexia as a "basket of issues" and said many people with dyslexia can experience difficulties with:
- phonological awareness (the connection between sounds and the letters that produce them)
- verbal memory
Dr John Rack, a member of Jim Rose's expert advisory group, said:
"This report represents a landmark for dyslexia in the UK.
"Finally, we have agreement on the definition of dyslexia, based on careful consideration of the research literature.
"That definition has been accepted by the UK's national dyslexia organisations and should therefore provide the clarity which has been lacking in the past."
The National Union of Teachers welcomed the report, but warned that training for 4,000 teachers might not be enough.
"While this is a good start, it is likely that we will require more teachers trained in the future to address the needs of children and young people coping with dyslexia," said its general secretary, Christine Blower.