A national register of people with cerebral palsy is being launched in a bid to help improve care for people with the condition in Wales.
Experts say the register is urgently needed so people with the condition get the services they need.
Campaigners say there is not enough information about the population of people with cerebral palsy.
The Welsh Government said it was supporting the development of the register.
Cerebral palsy is the name for a group of lifelong conditions that affect movement and co-ordination, caused by a problem with the brain that occurs before, during or soon after birth.
It is the most common cause of physical disability in children, affecting one in every 400 in the UK.
But the group setting-up the register said it was not known where people with cerebral palsy lived and what their different needs were.
Paediatrician Dr Rachel Lindoewood, co-lead on the project, said this could mean unidentified gaps in service provision across the country, which data collection would help to find.
“We hope the register will help us… work out where the resources need to be focused to bridge those gaps and get better outcomes for everybody with cerebral palsy”, she told the BBC’s Sunday Politics Wales programme.
“Potentially, by not having those services, people could end up with more complications from their cerebral palsy which could have an impact on their long term ability.
Read more at: https://www.bbc.com/news/uk-wales-politics-47414616