Cartellieri will be tasked with improving 's financial performance and the day-to-day running of the UK business, where she will report to Dermot Halpin, president of Expedia.
Prior to joining Expedia, Cartellieri was head of strategy at Kingfisher. She has also worked in consumer advice for and co-founded , where she was chief executive.
Halpin said: "Caroline brings a wealth of strategic expertise, commercial acumen and retail knowledge to Expedia.co.uk.
"I know that she will prove adept not just in maintaining our role as market leader, but will also ensure that we continue to be better placed than our competitors to take advantage of future opportunities."
Expedia's £14m UK account is handled by DFGW. The agency won the brief after a pitch against VCCP and Delaney Lund Knox Warren & Partners at the end of last year.
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