The new venture will be called Liftd (styled as LIFTd) and launches in January 2016. It will specialise in helping companies understanding the concept and importance of storytelling.
Dimelow is currently looking at securing flexible working space in London, however plans to be mostly mobile with his office.
The decision to depart GPJ after almost five years was inspired by his varied background in live experience strategy, internal communications and copywriting.
He said: "I’ve had an amazing four and half years at GPJ, filled with great work, talented colleagues and incredible opportunities. I’ve learned so much, not only about the industry, but also about my own place in it during that time, so I know I’ll miss being part of the business.
"That said, I feel like the company has been on a real journey for the last few years, and it’s now in such great shape as we head into 2016, so it feels like the ideal time for me to step aside. I’ve always left companies on great terms, so I’m sure we’ll have future opportunities to collaborate."
Kevin Jackson departed his role as vice president EMEA at GPJ in November, also to set up his own agency.
Blogs from Gareth Dimelow: Blog: Gareth Dimelow on the curse of content
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