The Children's Commissioner for Wales will today outline the importance of investing in youth services.
Keith Towler says shrinking council budgets could mean children's services don't get the right attention.
The Welsh Government says it's committed to developing effective youth services but says financial strains need to be acknowledged.
"It costs £35,000 a year to keep a young person in a young offender institution if they break the law" says Mr Towler.
"It costs something like £75,000 a year to run good youth facilities for 125 young people in the community."
"Now if you're talking about best value... there's real value in youth work."