The Mornington Health Centre in Dunedin and the Ropata and Karori Health Centres in Wellington have 50,000 patients among them.
Under the banner Cosine, representatives of the three practices met in Dunedin to hold their first combined Clinical Governance Group meeting.
Mornington PHO chief executive Barbara Bridger said all practices were stand-alone primary health organisations at the moment, but it was unclear how much longer this system would last.
As a result, there was much speculation about how primary care should be clinically led.
All practices recognised the economies of scale that could be achieved through being a large organisation, and she believed they were already on the way to becoming integrated family healthcare centres (IFHC), which the Government is keen to see established across the country.
IFHCs are groupings of GPs which are able to provide additional services to their patients, such as specialist nursing services, minor surgery and radiology.
The Clinical Governance Group meeting provided an opportunity for the three practices to learn from each other, find out what was working well and share success stories, she said.
"After all, the healthcare of a patient in Karori shouldn't be that much different from that of a patient in Roslyn.
"This meeting provides us all with a wonderful opportunity to share ideas among three very highly performing and successful practices in New Zealand.
"Why should we reinvent the wheel every time when we can learn from our colleagues in other parts of the country?"
