The London Review of Books has attempted to clarify comments made by Hilary Mantel about the Duchess of Cambridge, saying the author was actually criticising the media.
The Duchess of Cambridge, as Patron of Action on Addiction, is visiting the charity's Hope House treatment centre in Clapham, south London.
The Duchess of Cambridge has been defended by a charity chief executive after a scathing attack by novelist Hilary Mantel.
Nick Barton, who heads Action on Addiction, which Kate supports as patron, described her as an "intelligent" woman genuinely interested in the work of his organisation.
During a lecture, Mantel, the double Booker Prize winner, said Kate appeared to have been "gloss-varnished" with a perfect plastic smile, in contrast to Princess Diana, who she described as awkward and emotionally incontinent.
Kate is currently touring the addiction charity's Hope House treatment centre in Clapham, south London.
Asked for his reaction to Mantel's criticisms, Mr Barton said: "I don't think it's for me to comment on that kind of stuff. I speak of what I know - somebody who wants to help, is helpful and genuinely interested and is intelligent.
"I can only speak (of) what I know. I've met her several times and I found her to be engaging, I found her very natural, I found her actually genuinely interested in the subject."
Hope House offers a safe, secure and comfortable place for women to recover from substance dependence and receive additional support for other compulsive disorders.
It is the first time Kate has been seen in public after photographs of her on holiday in Mustique were published by foreign media.