The former Mindshare APAC MD will head up a fresh OMD regional leadership team with David McCallen as CSO and Matthew Ho as CCO.
Hagedorn has been with Omnicom since 2004 but is leaving the company.
Eileen Ooi was previously chief operating officer.
Integrated planning and buying remit is understood to be worth S$5 million.
Bharat Khatri was previously country head for India with Xaxis.
She departs from her CEO role at OMD after nearly five years.
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