Nancy Platts joins the agency having worked for Corbyn for the past 18 months, before leaving in the latest slew of departures from the leader's office. Another departure widely reported on Friday is Matt Zarb-Cousins, Corbyn's media spokesman.
Platts joins an agency which was formed by Francis, alongside two other former employees of the agency Claremont, in February last year. In January, it was named by PRWeek as one of seven new agencies to watch in 2017.
Francis had worked with Platts on her campaign to be elected as MP for Brighton Kemptown in the 2015 general election, which she eventually lost to Conservative incumbent Simon Kirby by less than 1,000 votes.
Platts said: "It has been an honour and a privilege to work for Jeremy Corbyn and the Labour leadership, but the time has come for me to move on.
"The Labour Party has been a large part of my life for nearly twenty years – from grassroots activist, then twice as a parliamentary candidate and now the Leader's Office. I will continue to support Jeremy’s leadership and want to thank him for giving me such an incredible opportunity - it has been an experience I will always value."
The Campaign Collective reinvests profits into small charities and community groups, and with Platts now has 14 "members", as its staff are known. Clients now include young people's charity Brathay Trust, social housing group QED and Stagetext, a charity that supports subtitling on stages.
Francis said: "Our members have worked with Nancy on and off for almost ten years and we are huge admirers of her principles, tenacity and campaigning skills. Nancy's experience will complement that of other members and help our social enterprise continue to broaden the services we can offer our clients in the charity, NGO and not-for-profit sector."
Platts was also Labour's candidate in 2010 in another Brighton constituency, when she also came second – to Green winner Caroline Lucas. Prior to 2015, she ran charity comms agency Campaign Machine, and has also worked for the London Fire Brigade and the charity Daycare Trust.
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