Switzerland gives its citizens the chance to play a direct part in political decision-making. Although direct democracy is not unique to Switzerland, it is probably more highly developed here than in any other country. Swiss citizens can either propose legislation of their own, or work to defeat legislation already approved by parliament.
A referendum is a nationwide vote called to challenge a piece of legislation already approved by parliament. If a group opposed to the new law manages to collect at least 50,000 signatures within 100 days of the official publication of the proposed legislation, it is again put to a nationwide vote. Such a vote is mandatory if the legislation involves an amendment to the constitution or if the government is proposing that Switzerland sign a major international agreement. (Michele Andina, swissinfo.ch)