Original article on BBC, here: http://www.bbc.co.uk/news/uk-wales-38001074
Local authorities in Wales have spent more than £56 million on external consultancy fees in recent years.
Isle of Anglesey council spent £9.8m in three years between 2013 and 2016, while Vale of Glamorgan spent just £875 in the five years up to 2016.
Nine councils failed to respond to a freedom of information request by Janet Finch-Saunders AM, the shadow cabinet secretary for local government.
The Welsh Local Government Association has been asked to comment.
"Whilst some specialist external advice is obviously warranted," said Conservative AM Ms Finch-Saunders. "The scale of this expenditure is eye-watering."
Wales' 22 councils have been dealing with Welsh Government budget cuts since 2013-14, and next year's £4.1bn budget will be the first increase in three years.
Cardiff council spent £8.8m in consultancy fees in the financial years between 2011 and 2016, while Caerrphilly spent £7.1m and Ceredigion £6.1m.
"Considering the vast array of civil servants and officers employed by local authorities, it is deeply disappointing that more has not been done to curb this expenditure," said Ms Finch-Saunders, AM for Aberconwy.
"It's simply unacceptable. Government expenditure of all types needs to be properly monitored and scrutinised, and we need to see greater openness and transparency, on top of a concerted drive to reduce the amount of taxpayers' cash spent on consultancy."