She will take over with immediate effect as business director, with operational control of the account. It was previously looked after by Mark Cadman, managing director of Lowe, who relinquishes day-to-day management of the account after four years, although he will retain management responsibility for the business alongside chairman Paul Weinberger, who created the "Every Little Helps" slogan.
"Leigh is ideal casting for Tesco. She has big brand experience and a track record of delivering great work. What makes her stand out is her energy, passion and drive to bring out the best in the people she works with," Cadman said.
Thomas has worked for M&C Saatchi for two years, where she was an account director working on the MG Rover and British Airways accounts. She comes from South Africa, and worked at TBWA and Jupiter Drawing Room at home before moving to the UK.
She will be running a team of 20 people on the Tesco account, which has been with Lowe since 1989. The agency makes around 20 television commercials, 2,000 press ads and 100 posters for the retailer every year.
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