O'Keeffe has been appointed as executive vice-president of operations and multi-country projects at TNS. He will be responsible for increasing efficiency across the agency and developing the company's overall global operations strategy.
He joins from GE Capital where he led several projects designed to drive process improvements.
Levin, meanwhile, comes onboard in January as executive vice-president of US consumer goods and services, TNS's largest client service sector. His task will be to build the division's business.
He joins TNS from the Aegis-owned Synovate where he worked as executive vice president of sales, marketing and client development.
O'Keeffe and Levin will report to Kimberly Till, president of TNS North America.
Till said: "Michael and Larry have clearly demonstrated their ability to deliver results and drive growth, so they will be valuable additions to the TNS Custom Research leadership team."
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