Lloyd Northover is one of the former Huntsworth shops sold to Media Square in November as part of a £63m deal, while MarketPlace was privately owned until acquired by Media Square in March 2004.
The merged company, which will operate under the Lloyd Northover name, will be led by Mike Taylor, Marketplace managing director, in the newly created role of chief executive, while Jim Northover will take on the role of non-executive chairman.
With offices in London, Oxford, Manchester, Barcelona and Dubai, Lloyd Northover will focus on brand strategy and communications and experiential marketing as well as PR, internal communications, events and architecture.
Taylor said: "In merging these long-established consultancies, we have brought together a highly talented team of people and an enviable client list. Given its scale and pedigree, Lloyd Northover will be an incredibly powerful force in the sector. This puts us in a great position to further attract and retain the best people and clients."
Neil Hudspeth, the former Lloyd Northover managing director, is leaving the business in the next few weeks to take on the role of CEO Asia Pacific with Enterprise IG, based in Shanghai.
Design and branding consultancy Lloyd Northover was set up 31 years ago in 1975 while Marketplace was established in 1985.
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