Traffic light coalition

Traffic light coalition (direct translation of German: Ampelkoalition) is a term originating in German politics where it describes a coalition government of the Social Democratic Party of Germany (SPD), the Free Democratic Party (FDP), and The Greens. It arises from the fact that the parties' traditional colours, respectively red, yellow, and green, resemble the normal colour sequence of a traffic light (Ampel). It has subsequently been used to describe similar coalitions between social democrats, liberals, and greens in other countries.

At a state level, there have been traffic light coalitions in Brandenburg between 1990 and 1994 and in Bremen between 1991 and 1995. Negotiations to form such a coalition upon the 2001 Berlin state election were not successful, likewise, preliminary talks after the 2010 North Rhine-Westphalia state election led to no result. Recently, a traffic light coalition was formed upon the 2016 Rhineland-Palatinate state election.

At a federal level, however, to date no government has been formed on this basis. Historically, there have been 'red-green' coalitions in the Bundestag between the SPD and the Greens, and social-liberal coalitions between the SPD and the FDP. However, whilst there may be common ground in terms of social progressivism between the three parties, the FDP's economic liberalism and long association at the federal level with the conservative Christian Democratic Union (CDU) make such a coalition problematic at present and the FDP chairman Guido Westerwelle had specifically ruled out this option for the 2009 federal election

...
Wikipedia