In a meeting with first minister Rhodri Morgan next month, council leaders will make the case for delivering services such as post-secondary education, business support and community regeneration, on the basis of their democratic mandate.
The Welsh Assembly is proposing to absorb the National Council for Education & Learning for Wales, the Wales Tourist Board and the Welsh Development Agency into its civil service.
The association believes there is a strong case for councils to take on responsibility for sixth-form education.
WLGA leader Alex Aldridge (Lab) said ELWa 'started off as a good idea but has now created an air of confusion in the provision of post-secondary education'.
He added: 'There is an opportunity here. We could make a hash of it, or we could make a damn good job of it by all of us sitting around the governance table together.
'Greater accountability and rationalisation doesn't simply mean centralisation, particularly as most quangos currently have a mixture of national, regional and local functions.
'There is a clear democratic mandate and a logistical case for local authorities to be central to the future quango debate,' he said.