Siân Berry

Siân Berry AM
Siân Berry in 2018
Leader of the Green Party of England and Wales
In office 4 September 2018 – 1 October 2021 Serving with Jonathan Bartley (2018–2021)
Deputy	Amelia Womack
Preceded by	Caroline Lucas
Succeeded by	Carla Denyer and Adrian Ramsay
Leader of the Greens in the London Assembly
In office 6 May 2016 – 19 October 2018
Leader	Natalie Bennett Caroline Lucas Jonathan Bartley Herself
Preceded by	Jenny Jones
Succeeded by	Caroline Russell
Member of the London Assembly
Incumbent
Assumed office 6 May 2016
Preceded by	Jenny Jones
Principal Speaker of the Green Party
In office 24 November 2006 – 30 November 2007 Serving with Derek Wall
Preceded by	Caroline Lucas
Succeeded by	Caroline Lucas
Personal details
Born	Siân Rebecca Berry (1974-07-09) 9 July 1974 Cheltenham, Gloucestershire, England
Political party	Green
Alma mater	Trinity College, Oxford
Website	sianberry.london

Siân Rebecca Berry (born 9 July 1974) is a British politician.

On 4 September 2018, she became Co-Leader of the Green Party of England and Wales alongside Jonathan Bartley. She stepped down from the party's leadership in October 2021. From 2006 to 2007, she was one of the Green Party's Principal Speakers.

She was the party's candidate in the 2008 London mayoral election, and again in the 2016 election, at which she came third.

She is a member of the London Assembly and the only Green Party councillor on Camden Council, representing Highgate.