Donaldson, who was previously the head of sales research at BBC World, will be responsible for developing industry research initiatives and working closely with agencies and advertisers on the benefits of regional press.
Reporting to Robert Ray, the Newspaper Society's marketing director, Donaldson will take up his new role early next year.
Before the BBC, Donaldson worked as the insight and accountability director at MediaVest and also held positions at Saatchi & Saatchi and the Financial Times.
Ray said: "I am delighted to have someone of Keith's experience on board and his agency and media-owner experience across a range of communication channels will be a huge asset to our agency-and-advertiser dialogue."
The Newspaper Society is working on a major research project with gfk/NOP on how regional press fits into people's lives. It is also holding its first conference for advertisers and agencies next June.