Leah (pictured) stepped down from her role at Weber Shandwick last year, following 20 years at the helm. She was replaced by Heather Blundell, who had been acting MD since March 2016.
Leah said: "It's a great time to be a woman opening a business in my 50s with the benefit of 30 years in MD posts behind me and the experience of managing senior client relationships for over 25 years."
Her new venture, The Little Big Agency, "will focus on building reputations for companies, brands, people and places" via strategic comms, consultation and activation, Leah said.
Leah said the agency has launched with a number of clients, including two regionally based food-and-drink businesses, although she declined to identify them.
Leah has also made an agreement to collaborate on client work with littleBIG Marketing & PR in Australia, which was founded by Sally Harley 10 years ago.
"Sally's agency focuses on food & drink and tourism, which is one of my specialties, so she was really happy to start working together - it's just coincidence that our agency's share the same name," Leah told PRWeek.
The new agency, which launches today (13 March), has four staff including Leah, who said she is also looking to add a non-executive role to her portfolio.
Before joining Weber Shandwick, Leah ran Lawson Leah Communications, which she founded in 1987. The business was bought by Weber's parent company IPG in 1997.
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