Australian traffic management company Altus Group has bought Traffic Management NZ, as part of regional expansion plans.
The value of the deal has not been disclosed.
Pacific Equity Partners owns a major stake in Altus, which has more than 4000 staff and 2000 vehicles in 28 Australian locations, compared with Traffic Management NZ's (TMNZ) team of 500 in 19 New Zealand locations.
Altus Group chief executive Ben Marsonet said entering the New Zealand market was a long-term strategic goal.
"We are delighted to have the opportunity to work with TMNZ, to continue to invest in its people, systems and capacity - and to deploy our priority digital solutions to further improve safety on New Zealand's roads," Marsonet said.
"This investment in TMNZ is significant for the industry, as it gives TMNZ management good firepower to continue to build its New Zealand platform, and eye further, strategic local merger and acquisition activity."
TMNZ managing director Dean Kebbell said the Altus buyout would enable the business to grow and to retain its staff.
"The size of the opportunity in front of TMNZ is significant and requires investments, systems and structures that would be difficult for us to deploy alone."