Merging education and other council services will not necessarily save money, Scotland's leading director of education has warned.
Leslie Manson, director in Orkney, and president of the Association of Directors of Education in Scotland, said that mergers might "please local punters" but they required significant investment.
"I can't see that piecemeal solutions where pairs of councils start thinking about this is the way ahead. The critical mass you need to guarantee savings would probably require a national strategy," he said.
Mr Manson's comments, which he stressed were his own personal views, followed revelations that East Lothian and Midlothian councils are in talks that could lead to the merger of their education departments, billed as "Scotland's first joint education authority".
East Lothian Council leader Paul McLennan stressed that the authorities were just "scoping out" what a joint education service would look like, and the move had yet to be agreed politically. The priority was improved standards rather than efficiencies, he insisted.
Sir John Arbuthnott, author of the Clyde Valley Review which examined how eight councils in the west of Scotland could share services, welcomed the move.
He disagreed with Mr Manson. In two relatively small councils, it would be "valid to look at the extent to which you need a duplication of officers", he said.
Potential areas for shared management or planning for education highlighted in the Clyde Valley Review were school transport, school buildings, supply teachers and specialist services such as psychological services and special needs.
However, the Clyde Valley authorities, which are soon to publish progress reports, were not looking at merging education services, said Jim Fletcher, East Renfrewshire Council leader and its former education convener. "If a director is working for East Renfrewshire, I expect them to be committed to delivering for East Renfrewshire Council," he added. "It's difficult for senior people to serve two or more masters."
Savings could also be "illusory" and schools could suffer from a less supportive and responsive service, he believed.