Siân Rebecca Berry (born 9 July 1974) is a British politician who served as Co-Leader of the Green Party of England and Wales alongside Jonathan Bartley from 2018 to 2021, and as its sole leader from July to October 2021. From 2006 to 2007, she was one of the Green Party's principal speakers. She was unsuccessful as the party's candidate in the 2008 London mayoral election, the 2016 election, and the 2021 election. Berry has been a Member of the London Assembly (AM) for Londonwide since 2016, and is also a Green Party councillor on Camden Council, representing Highgate. She has been selected as the party's candidate for the Brighton Pavilion constituency, whose MP since 2010 has been the Greens' Caroline Lucas who is retiring. (Source: Wikipedia.org, CC BY-SA)