District health boards in Wellington, Wairarapa and Hutt Valley are to integrate their hospital and community lab services.
Planned changes to lab testing in the region have sparked fears from senior doctors about possible privatisation.
The DHBs said they had decided on one management structure and process across the region.
They said it would lead to more consistency, efficiency and savings, and the next step was to choose a preferred provider.
The changes would take effect in November next year.