The Green Party has launched a national billboard campaign urging people to "vote big, vote brave".
To mark the poster launch Natalie Bennett, the party leader for England and Wales, met up with parliamentary candidate Caroline Lucas in Brighton.
Ms Bennett warned voters "the time for half measures is over" and urged people to "vote for what you believe in".
She said a Green vote would ensure big firms and rich individuals would pay their "fair share".
Ms Lucas, who became the UK's first Green MP when she was elected in 2010, added: "We have a bold message that will resonate with the people of Brighton and Hove, and across the country.
"Only the Green Party is willing to stand up to the establishment parties on issues like climate change, a resilient economy and protecting the NHS."
'Fit for the 21st century'
The Green Party has vowed to put up the top rate of tax to 60p in the pound, which Ms Bennett said would bring in an extra £2bn a year for public services while acting as a disincentive to firms paying "excessively high salaries".
She added that her party wanted to call for a review of all "commercial animal racing", saying there were animal protection issues which needed to be addressed.
- Phase out fossil fuel-based energy generation and nuclear power
- Reduce all UK greenhouse gas emissions to 10% of their 1990 levels by 2030 to tackle climate change
- Invest in renewable energy sources, flood defences and building insulation
- Ban fracking
"We should be spending our money on public services that meet our essential needs, we should be spending our money on building council homes, homes for social rent.
"We need to invest in renewable energy, energy conservation, there is a whole range of things we need to do to make British society fit for the 21st century," she said.
The Greens have also proposed a "wealth tax" which would be 2% a year levied on people with assets of more than £3m which, Ms Bennett has claimed, could bring in £25bn a year "by the end of the Parliament".
Brian May, the lead guitarist of the rock band Queen, also joined Ms Lucas in Brighton to talk about democracy and the importance of voting - promoting his own "Common Decency" campaign as well as publicly backing Ms Lucas.
Mr May said voting Green might not always be the best option and could be a wasted vote.
He said: "I would have to confess to having a leaning towards Green.
"An awful lot of people would like to vote Green but feel that it is a wasted vote so what I'm saying is, in a sense, is I am not going to promise to ask people to vote for every Green candidate because in some cases strategically it may be better off doing something different."
A full list of candidates for Brighton Pavilion can be found here.
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