Formerly an associate director in the Fishburn financial team, he will report to Stefan Lutz, Allianz Global Investors’ Frankfurt-based European head of communications, and will be based in London.
Fairbrother’s appointment to the new role comes as the investment management company looks to grow its presence in the UK.
Commenting on Fairbrother’s appointment, Allianz Global’s head of global communications John Wallace said: "Allianz Gi is a relatively young company which needs to raise its profile in a number of markets, including the UK.
"Alastair has the experience in financial services PR to help the company’s achieve this objective."
Allianz Global Investors has 23 offices in 18 countries and employs more than 500 staff.
Before working at Fishburn, which is now actively looking to fill the associate director role, Fairbrother worked with Wallace while acting as a press officer at the London Stock Exchange.