Ankit Gupta, who only joined the firm six months ago, will lead the region from New Zealand.
Andrew MacFarlane will be chief financial officer from August 2.
Dr Charles Hyde will be head of asset allocation from July 1.
St John will replace Tony Carter, who will retire from the board in August.
Kelly-Ann Maxwell has been appointed CEO of Ogilvy Network NZ.
CFO Matt Smith joined Bobux mid-Covid lockdown in 2020.
Jeffrey Clarke has been appointed as chief executive after being interim CEO since April.
Jonathan Gillard is a senior partner at the firm.
Effective from September 1, Mark Chellew joins Downer as an independent director and chair-elect.
Clarke Hill brings more than a decade of experience.
