Education leaders are securing the majority of new children's services directors' jobs, according to latest figures.
Of the 78 appointments made so far, 60 have gone to former heads of education, and 17 to their social services counterparts. The previous experience of one successful candidate was unknown, the survey from Confed, the professional association for children's services managers, shows.
Sarah Caton, Confed's assistant director, said she expected the balance to even out as more appointments were made.
"Both sectors have been concerned about expertise disappearing from their fields, but what we do not know is how the staffing levels beneath directors will look. One would expect that this expertise would be evident in the tiers of management below the directors," she said.
The shake-up arises because of the Government's Every Child Matters policy, which pressures local authorities to integrate education, health and social services, in the wake of the Victoria Climbie case, and requires them to appoint directors of children's services by 2008.
Several high-profile directors of education have already left or will be replaced in the near future.
They include David Cracknell, from Cheshire, Andrew Seber from Hampshire and Mick Waters from Manchester local education authorities.
They have been replaced respectively by Jim Crook, John Coughlan and Pauline Newman, all of whom have social care backgrounds.
The figures show there is a concentration of former social services directors being appointed in the north of England.
Darlington, Newcastle, Northumberland, South Tyneside and Stockton have all appointed former social care chiefs, as have Bury, Cheshire and Rotherham.
In the south-west however, almost all appointments have been from education, including Bristol, Cornwall, Devon and Somerset.
In the capital, only eight of the 33 boroughs have appointed children's services directors.
A separate study of 116 of England's 150 social services departments early this month found a quarter of councils that have appointed children's services directors chose social care professionals. This was a rise on last October, when just one-sixth of appointments were from the sector.
The study, by Community Care magazine, raised concerns about the exodus of social care leaders. One-fifth of those not appointed planned to retire, it said.
Andrew Christie, of the Association of Directors of Social Services, said the figures could be skewed by some former directors taking on new posts for adult social services.
Earlier this year, the Commons education select committee warned the Government to pay close attention to the appointments. In a report on the Every Child Matters strategy, it said there was a danger that directors of children's services might not know enough about the social care side of their responsibilities.
Last year's Children Act provided the legal base for the Every Child Matters reforms, which include plans to set up a national database of children.
Further legislation to improve child protection is due to be debated in Parliament later this year. The Safeguarding Vulnerable Groups Bill will be based on the recommendations of Sir Michael Bichard's inquiry into the Soham murders and is expected to propose a new system for registering teachers and other adults who work with children.