The Wisconsin Green Party is an active member of the Green Party of the United States. In 2006, the party helped place antiwar initiatives on the ballots in 32 towns (24 of which passed those propositions). WIGP member Ben Manski is a former co-chair of the Green National Committee.
The WIGP emerged in the late 1980s when several independent local Green groups combined. Walter Bresette and Frank Koehn of the Lake Superior Greens were instrumental figures in the early years of the party's development. Koehn's election to the Bayfield County board in 1986 was the first time a Green Party candidate had ever been elected to an office in the United States. Dennis Boyer, Richard Latker, Joyce Melville and others established a large chapter in Madison that brought together veteran activists (many of them refugees from the Labor-Farm Party, which disintegrated in 1987 after Greens and Marxists in the party failed to agree on a platform) and student activists affiliated with the UW-Madison Greens.
In the spring of 2006, nine of 13 Green Party candidates won races in which they ran. John Hardin (Barron County), Ben Farrell (Winnebago County), Bob Ryan (Door County), Barbara Vedder (Dane County), John Hendrick (Dane County), and Kyle Richmond (Dane County) all won re-election to their respective county board seats. Vedder had been appointed to an open seat a few months before the election.
Jeff Peterson (Polk County) and Ashok Kumar (Dane County) took their seats as county board officials for the first time, as did Eric Krszjzaniek (Portage County) who won a recount of write-in votes with an original 5-7 loss turning into a 8-3 win.
On April 3, 2007 a further seven out of 14 Green Party candidates running for office won their elections throughout Wisconsin. This brought the total number of elected Greens in Wisconsin to twenty-two. 
- Website of the Wisconsin Green Party
- Press release on Iraq antiwar initiatives
- Forum on Green Party elections, Spring 2006