Dimelow, who was formerly executive director, engagement planning at the agency, will launch his new venture ‘Liftd’ in January 2016.
Dimelow spent four-and-a-half years at George P Johnson, having joined from competitor Jack Morton Worldwide where he held the position of VP, Experience Director.
Dimelow told C&IT: "I've been inspired to set up my own company from the conversations I've been having with start-ups that don't seem tohave a strategic marketing approach. After giving insight into how they should be talking about their business, I started to think of a model that I could propose to businesses myself.
"When I look back on my four-and-a-half years at George P Johnson, I've learned more at that company than I have done anywhere else. Having always been a part of big agencies, I'm now looking forard to learning how to work by myself as part of my own business."
The announcement follows the departure earlier this year of former George P Johnson vice president Kevin Jackson, who left to form his own agency The Experience is the Marketing.
"I'd like to think that there will be opportunity to work with Kevin in some capacity in the future," Dimelow added.
While he is currently looking to secure some office space in London, he has stated that his office will be mostly mobile.
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