The Auditor-General has released a report critical of district health boards' efforts to work together in order to save money and improve treatment.
The Government introduced a policy in 2009 to increase collaboration within and between DHBs.
Auditor-General Lyn Provost said she expected to see tangible benefits for patients and taxpayers by now but there is little evidence that is happening.
Ms Provost said there were not enough skilled people to give DHBs advice when making critical decisions and found there was a lack of reliable data which boards could use for planning.
She said the Ministry of Health needs to do a better job of giving guidance to boards.