Barker was head of corporate communications at JWT and had just been appointed to take over a senior communications role at JWT's WPP parent when she fell ill.
Starting out as a newspaper reporter in her native Australia, Barker sustained her reputation as a tenacious news gatherer when she joined Campaign.
Bernard Barnett, a former Campaign editor, said: "As a reporter, she had the Australian terrier instinct and never let up on a story until she was satisfied she'd covered every angle. When she was editor, she presided over the newsiest content in Campaign's history. As a person, she was simply lovely.
After quitting Campaign, Barker spent a period as the advertising columnist of London's Evening Standard.
Barker is survived by her husband, the former agency boss Mike Townsin, and their son and daughter.
Campaign will be publishing a tribute to Barker this week. Please email your memories of her to firstname.lastname@example.org.
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