There are fears that district health boards are putting patients' lives at risks by refusing to hire more staff.
Sam Holford from the Resident Doctors Association (RDA) says it's only a matter of time before something bad happens.
"Patients could be paying with their lives. If a doctor makes a mistake related to fatigue, then working too many hours in a row and too many nights in a row, could contribute."
They're fed up with the "false promises" being made by health boards.
"They do a review and we can all agree we are short a number of staff," says Dr Holford. "They won't make the extra step of saying, 'We will now actually fill those roles.'"
The RDA has singled out the Waitemata and Counties Manukau DHBs. Instead of working seven 10-hour night shifts in a row, they want a maximum of four. And rather than working 12 days in a row with only two days off before returning to work, they want a maximum of 10 days, with four off.
Waitemata will need another 19 or 20 doctors to fill the roster, says the RDA.
"After several years working to get some improvements implemented we are still far too far away from resolving all the affected rosters - the rate of change is simply too slow."
Mediation between the RDA and the district health boards will take place on September 12.