The reforms, set out in the Green Paper Every Child Matters, are the Government's response to the inquiry into the death of Victoria Climbie.
They propose integrating key children's services such as education, social services, health and Connexions under children's trusts. The new trusts will be part of local authorities and be answerable to elected members.
But the reforms have sparked a debate about their implications for the Government's advice and guidance service for 13 to 19-year-olds. Connexions was introduced by the Government to ensure that teenagers stay in education, training or work. It was built on the legacy of privatisation of local authority-run careers services by the Conservatives, which has resulted in the service operating differently in different areas. In some parts of England, services to young people are delivered directly by partnerships, while in others they are contracted out to private careers companies.
Critics of Connexions have accused it of failing to give adequate career guidance in schools and colleges because it is focusing on government targets to cut numbers of disaffected young people.
Carolyn Caldwell, executive director of the National Association of Connexions Partnerships, said some fear that the new reforms pave the way for a local authority take over. "The most feared impact is that, like other attempts to provide preventative services, it will get soaked up into a small number of children who have the most need."
She said such a takeover would be a major and complex exercise. "In doing that we would lose momentum and divert energy. We want to spend our energy delivering services to young people. And there's a strong view that actually, it's not broken so we don't need to fix it."
Allister McGowan, chief executive of VT Careers Management, England's biggest career guidance provider, said he feared the reforms could mean less money for his service.
"It's impossible to argue with the thrust of the Green Paper in terms of its child protection agenda," he said. "The concern is not about that. It's about what potentially gets lost and how that damages some of the lifelong learning and education agendas."
The Local Government Association said it was delighted at any moves towards better integration of services for children. "We believe it is right for local government to have the lead role for children's services and to be ultimately accountable for these," said a spokeswoman.
A Department for Education and Skills spokeswoman denied that the Green Paper proposals mean a change to the structure of Connexions. "Children's trusts will be the focus of further improvements to joint working, planning services and pooling of budgets," she said. "And given the importance of Connexions to children's services, it is important that they work together well."