He takes the role of vice-president of global marketing and research at the newspaper group, which publishes 28 newspapers in 16 countries. Metro is famous for its freesheets, distributed at commuter points in major cities, and is listed on the Stockholm bourse.
Constantine said: "Metro has an extremely strong global market position and a unique reader profile. My job is to establish a fully-formed marketing function across the network to maximise the enormous potential of the Metro brand to readers and advertisers. It's an exciting opportunity."
At the same time, the company announced a raft of new managing director appointments in various regions. These include Svenn Dam, who becomes managing director of Northern Europe, and Carlos Oliva-Velez, who is named managing director of Southern Europe and Latin America.
Metro president and CEO Pelle Tornberg said: "This reorganisation reflects the global nature of the group and our business relationships. The new structure combines our existing pool of proven management talent with the recruitment of highly experienced new managers."
Constantine was at News International until 1999, when he quit to form the mobile phone chat room company TalkCast with fellow News International executive Ellis Watson, founder of Currantbun.com.
He joined as marketing manager of News Group Newspapers in 1992, became marketing manager of Times Newspapers in 1995 and was promoted to marketing director a year later. Before joining News International, he was an account manager at Allen Brady & Marsh and the sales promotion agency Option One.
Metro also said that it had appointed Per Mikael Jensen as international chief editor and Silvio de Groot as head of online advertising sales. The company is headquartered in Luxembourg.
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