He told the 650 IRRV delegates the tendering exercise was about more than saving money.
'We are not going to impose a CCT regime which makes it harder to operate a good service. It must allow selection based on quality, and not just price', he said.
The DoE was working hard with the local authority associations and professional bodies to get the balance right, he said.
'Parliament will have imposed that restriction for a reason and CCT requirements cannot override it.
'I hope my support for quality as a criteria will allay some of your concerns', he said.
He expected to publish proposals next July for contracting out finance services. But he said they would not force councils to tender part of every service in the finance arena.
Mr Curry thanked institute members for implementing council tax so smoothly and disappointing the government's critics.
He paid particular tribute to the practical advice the institute offered the DoE when it was planning the new tax.
He emphasised the extensive co-operation between the DoE and councils on legislative changes and promised his attitude would not change now the council tax was working smoothly. He believed relations between councils, government and professionals were on a positive course. He offered to help some councils involved in legal battles over business rates revaluation.
'We accept that those in the firing line on important legal principles might need some extra help with costs', he said.
At a press conference before his speech, Mr Curry played down the importance of the DoE memorandum leaked in last week's LGC which showed council tax payers in shire areas faced rises of up to £100 in their bills to pay for the transitional costs of restructuring local government.
'We have not made up our minds how that will be financed', he said. He denied such a sharp hike in bills conflicted with the principles of capping.