Colin Hughes, who has been with GNM since 1998, has held a number of senior management roles with the publisher, becoming managing director of Guardian professional in 2006.
In his current role he heads the B2B unit, which focuses on services to the media, education and public services professionals. He also oversees the digital recruitment revenues and sits on the GNM executive committee.
He will leave GNM in January 2012, after he has restructured the department. GNM is now on the hunt for a replacement.
No further details of the proposed restructure have been disclosed by GNM.
Adam Freeman, GNM's executive director commercial, said the B2B unit was "predominantly a digital business, with more than half its revenues coming from online recruitment advertising, sponsorship and research products."
Separately, GNM's head of events Charlotte Gooch is to leave the business. She has been in her current role for nearly two years and has been with GNM since 2006.
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