There has been debate about the size and structure of local government in Scotland since at least the 1960s, but it has gained urgency in recent months.

This is partly because almost everyone agrees that however the referendum goes next year, the status quo on councils will not be acceptable after 2014. There is change coming to local government; the only question is: what kind of change?

Ahead of the first meeting of a new commission into the subject, David O'Neill, the president of the Convention of Scottish Local Authorities (Cosla) which represents all 32 Scottish councils, has pitched in with his contribution. Mr O'Neill says local people should be given a greater say in the decisions that affect them and complains that there has been a move away from local decision-making. The destination of his argument is clear: more powers for local authorities.

The problem is that there appears to be two distinct pressures at work in this area. On the one hand, there is the growing pressure from councils, in particular the island councils, for more powers. On the other hand, the Scottish Government (whatever lip service it may pay to more local devolution) has demonstrated a centralising tendency. And behind this tug-of-war is the question that has been getting louder and louder: does Scotland need 32 councils?

It is clear that, as the new commission prepares to meet for the first time this week, council leaders are keen to emphasise the option of greater powers and play down talk of reducing the number of councils. But if the commission is to be taken seriously, it must give consideration to the question of the size of local government. The leaders of Scotland's councils have made a convincing case for more powers - most recently Gordon Matheson for Glasgow - but greater powers cannot be handed to councils without a deeper consideration of their role, function and costs as well as how many councils Scotland needs.

A few councils have already responded to this question with some merger of backroom services and other overlapping areas but despite calling for greater powers through its Local Vision manifesto, Cosla has proved resistant to the reform that must accompany such powers. Giving councils more powers could unlock greater economic potential for some communities, but it must go hand in hand with a reduction in the number of councils and greater merger of services and staff.

There would naturally be upfront costs associated with such a change, as there was with the creation of the single police force, but the potential benefits would include savings that could help tackle the gap between the demand for services and what councils can afford. There would also be greater efficiency in delivering vital social services by removing liaison between different departments.

And there is another important potential benefit of widespread reform. Mr O'Neill says local government has failed to spark the public's imagination and the shockingly low turnout in local elections would seem to prove it. What the creation of fewer, more efficient councils with greater powers could do is change that and perhaps get Scotland's voters interested in local democracy again.