The appointment is the first to be made by Chris White-Smith, who was promoted to group sales director as part of the changes.
White-Smith said: "I am delighted to be appointing Stephen as director of classified. He's perfect for our plans going forward and absolutely deserves the chance to shape and implement the future of the department and its integration with other Telegraph properties. I'm thoroughly looking forward to working with him."
Dunk, who has been at the company for 16 years, takes on a number of tasks previously carried out by former deputy ad director and commercial director of Hollinger New Media, Mark Payne, who has been promoted to group commercial director.
Dunk's remit includes managing the 90-strong sales team, with 10 sales managers reporting to him.
He will oversee sales on the paper's main supplements including Motoring, Property, Arts+Books, Travel and Business, as well as developing cross-selling opportunities across the Telegraph Group's enterprises, commercial development, promotions and divisions outside of classified sales.
Dunk said: "I'm thrilled to be given this opportunity at a time when there are so many new options available to clients. Telegraph Group has always been quick to adapt to changing environments and, where appropriate, we are keen to develop flexible access to all our media channels, with classified playing an integral part."
He will continue to work closely with editorial and focus on maximising revenues through existing franchises and developing new revenue streams.
Dunk joined the Telegraph Group as telesales executive, moving to the position of telephone sales manager. In 1995, he was promoted to Travel Group head and, in 1997, he became classified sales manager.
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