In the newly created role of head of integration, his brief is to ensure effective operation of a central hub of consultants which plans client projects with assembled talent from across Chime's network.
Leach, who was the head of strategy at Chime's former HHCL & Partners subsidiary, will work closely with Sue Farr, who joined Chime earlier this year as the chairman of its advertising and marketing services division.
The division includes Pure Media, Roose, Heresy and the Will Pond-Jones Collective and has clients such as Nestle, Carphone Warehouse ad Madame Tussaud's.
Leach's arrival comes as Chime struggles to get back on an even keel after a 28% drop in pre-exceptional operating profit to £3.61m in the six months to the end of June. Lord Bell, the Chime chairman, said he was "extremely cautious" about the group's prospects.
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