Hemmings will be responsible for developing the Amscreen brand as it continues to grow internationally.
He will report to Chris Forrester, European managing director of sales and marketing, Amscreen.
Hemmings, who joined CBS Outdoor in July 2006, rose from senior marketing manager to head of marketing, where he was responsible for marketing strategy across the CBS Outdoor portfolio of rail, Tube, bus, retail and airport media.
Prior to joining CBS Outdoor, Hemmings was at FHM and Heat magazine-owner Emap (now Bauer Media) as acting head of trade marketing. He started his career at Independent Newspapers as a sales and marketing executive.
Forrester said: "We are extremely pleased to welcome Mike to Amscreen. His experience will no doubt be a great asset to the company as we continue to expand and build the brand internationally.
"Together with other recent appointments to the Amscreen team, we're sure Mike will help to enhance our position as a leader in European digital media and I look forward to him joining the team."
Hemming's appointment follows Amscreen's hiring of former JCDecaux director Yoko De Souza as director of client sales and Winfried Karst, formerly chief operating officer of Germany and chief executive of Switzerland at Kinetic, as its chief executive, central and Eastern Europe.
Amscreen bought the sales and marketing operation of its digital out-of-home ad sales house Digicom in August last year, following a deal to expand its digital signage to BP-owned petrol forecourts in Europe.
Hemmings will join Amscreen in February. A spokesman for CBS Outdoor had not confirmed whether Hemmings would be directly replaced by the time of publication.
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This article was first published on mediaweek.co.uk