From the New Year, Andrews will assist all group programmers and editors at the UK's largest commercial radio group in implementing network programme strategy.
He will report to director of broadcasting, Richard Park.
The current deputy programme director was part of the team which launched the Capital FM network across the UK in January 2011.
Park said: "Gareth's outstanding track record speaks for itself. His enthusiasm, commitment and vision will be integral to Global Radio as we strengthen our position as the UK's largest commercial radio group. We wish him every success in his new role."
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