The rising cost of social care could force some councils to merge, according to the chief executive of the Welsh Local Government Association.
Steve Thomas said social care costs were expected to double over the next 15 years.
But he said overall council budgets would continue to decline.
He said he sometimes wondered why people wanted to be a councillor.
“It’s difficult, it’s thankless,” he said.
“People don’t usually stand for office to cut services but that’s what they’ve had to do over the past five years and that has been and is going to be their job.”