Aimee Buchanan hires former colleague, Melissa Hey as Seb Rennie replacement

GroupM has appointed OMD’s chief investment officer, Melissa Hey as its replacement CIO for Seb Rennie, who is set to join LiSTNR.

This marks another hire for Aimee Buchanan from her old agency after joining in late-2021. Nathan Young, OMD’s ex-chief operating officer also joined the agency prior to Buchanan starting in 2021, with Mike Worden also moving across in 2021, lasting a year before moving client-side. 

Hey joins her old boss at GroupM

Hey has been chief investment officer at Australia’s biggest media agency since 2017, promoted into the role by Buchanan, and together continuing to build OMD into its market-leading position. In her new role, she will oversee investment and partnerships, leading GroupM’s Responsible Investment Framework, as well as working with EssenceMediacom, Wavemaker and Mindshare’s investment teams.

She will also join GroupM’s executive committee, reporting to Buchanan.

Buchanan said: “I’ve had the pleasure of working with Melissa in past roles, and I know she will be a fantastic addition to our team and will bring immense value to our agencies and clients. We are thrilled to bring her expertise, gravitas and capability into the business to lead our Responsible Investment approach and help us shape the next era of media. She is passionate about the evolution of investment and GroupM’s vision of making advertising work better for people and will continue to evolve how we use our scale for good.”

Hey said: “I’ve absolutely loved my time at OMD, but the opportunity to take on a new challenge and step into a group role and lead investment strategy for one of the largest media agency networks in the country was unmissable. I’m excited to join the team at GroupM and looking forward to being part of the global vision to make advertising better for people. I’d like to thank everyone at OMD for being an amazing team to work with over the past 12 years. They are a talented team and I have no doubt they will continue to see great success.”

OMD is yet to appoint a replacement.

Hey is replacing Seb Rennie, who is making a surprise move to SCA’s LiSTNR

On Hey joining GroupM, co-CEO of OMD, Sian Whitnall told Mumbrella: “Melissa has made an incredible contribution to OMD in her time with the business. She leaves us with the legacy of developing a best-in-class investment product and has been instrumental in driving significant results for OMD and our clients, all delivered with complete transparency. We thank Melissa immensely for the years of dedication and loyalty she has given OMD and wish her all the best in her new challenge.”

“We have commenced work on a succession plan and have the bench strength of talent in place for the continued success of OMD and our clients.”

Hey spent 12 years at OMD, before then holding roles at Starcom and Carat.

It has been a busy start to the year for GroupM, also appointing a new CEO at EssenceMediacom last week, in Pippa Berlocher. It has also made a number of recent senior hires outside of Berlocher, including Tom Braybrook to help launch Acceleration, Matt Scotton and Stephanie Douglas-Neal.

This also includes a number of major senior changes since Buchanan’s arrival, with a new Mindshare CEO in Maria Grivas in 2022, as well as Scott Laird as its chief people officer, amongst other hires.


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