Trevor Sargent, who resigned as Minister for Food and Horticulture today, has been a member of the Green Party since 1982.
Mr Sargent (49) was first elected to Dublin County Council in 1991.
In keeping with party policy on dual mandates, he resigned his council seat on his election to the Dáil for the Dublin North constituency at the 1992 general election.
He was elected leader of the Green Party in October 2001 and held the position until his resignation following the party's entry into Government with Fianna Fáil in June 2007. He was succeeded by John Gormley.
He was then appointed to the role of Minister of State for Food and Horticulture by then taoiseach Bertie Ahern.
Mr Sargent famously caused uproar in the Dublin County Council chamber in February 1993, when he produced a £100 cheque which he said he received from a developer seeking to rezone land.
The Green TD waved the cheque above his head and asked if any other councillors had received such payments. According to the contemporary report in The Irish Times, several councillors surrounded Mr Sargent and demanded to see the cheque.
Fianna Fáil’s Don Lydon was reported to have grabbed him around the neck and tried to wrestle the cheque from him. Senator Lydon later dismissed the incident during evidence to the Flood tribunal as "a bit of craic" and "pure divilment".
A member of the Church of Ireland, Mr Sargent is a fluent Irish speaker and committed environmentalist and runs a blog on growing organic food.