More than 37 million copies of the British-born author's murder mysteries have been sold since he penned his first novel 15 years ago, netting him about $1 per copy in royalties.
He is recognised in the street.
He sits next to people on planes who are reading his books.
Hundreds turn out to "meet the author" nights like the one that was held at the Dunedin Public Art Gallery last night.
His central character, the enigmatic ex-military policeman Jack Reacher, has become public property.
But Child - real name Jim Grant - never takes his readers for granted.
About 175,000 new titles were released globally every year and there were still 2.3 million English language titles in print, he told the Otago Daily Times yesterday on the last day of a month-long tour to promote his 14th novel.
A voracious reader himself, he said he did not persist with a book if it did not appeal within the first 20 or 30 pages and he knew other readers were the same.
It was a writer's obligation to satisfy the reader - to provide them with an emotional payback, he said.
"I'm not so worried that they might have paid a few dollars for the book.
"But readers can never get back the time they have spent reading it."
It does not seem Child has any worries on that score.
He takes a year to write each one and readers tell him they devour them in as little as one evening.
Child, who lives in New York, wrote his first book after redundancy from 18 years in television.
He said he knew he could write reports and memos and always believed he could write a book.
"But there was a barrier there.
"There was a fear of exposure, like standing in public naked."
The loss of his job and income were the motivation he needed, he said.
"I certainly would not have done it as a hobby just to fill in the time after my day job.
"Because it was totally necessary to succeed I did it and did it well."
