Harrison's promotion, which took effect at the start of the year, follows Asia-Pacific CEO Alan Couldrey taking on the role of chief talent officer at Ogilvy in addition to his Brand Union role.
With the expansion of Couldrey's role, Graham Hitchmough was promoted from CEO of Southeast Asia for Brand Union to include South Asia, while Monica Lee, CEO of China, added North Asia to her remit.
With Hitchmough and Lee focused on geographic remits, there was a need for someone to take on strategic planning for the agency as a whole, explained Harrison. "The short- to medium-term planning is covered, so I was brought in to help determine where we need to be in, say, five years."
In his new role, based out of Hong Kong, Harrison will retain responsibility for the region's key client relationships but will also take an overview on business strategy for the region including mergers and acquisitions, geographic expansion and corporate best practice.
"Geographically speaking, we are looking first at markets in the region where Ogilvy is strong but as yet does not have a Brand Union office," said Harrison. "Two such markets are Manila and Ho Chi Minh. We're also trying to determine if it makes sense for our China office to expand other cities such as Guangzhou and Shenzhen."
According to Couldrey, Harrison was selected for the role based on his extensive experience and insight into client needs across the region.
Prior to joining Brand Union in 2013, Harrison held a series of senior client roles in Europe as CEO of Müller and was also a marketing director at Nestle, Coca-Cola and Procter & Gamble. Most recently, he was the Founding CEO of RadioCentre, the trade body for UK commercial radio.