The 1955 system, also known as the one-and-a-half party system, is a term used by scholars to describe the dominant-party system that has existed in Japan since 1955, in which the Liberal Democratic Party has successfully held by itself or in coalition with Komeito a majority government nearly uninterrupted with opposition parties, other than for brief stints in 1993–1994 and 2009–2012, largely incapable of forming significant or long lasting alternatives. Wikipedia