The Social Democratic Party is the largest social democratic political party in Romania and also the largest overall political party in the country, aside from European Parliament level, where it is the second largest by total number of political representatives, after the National Liberal Party (PNL). It was founded by Ion Iliescu, Romania's first democratically elected president at the 1990 Romanian general election. It is currently part of the National Coalition for Romania (CNR), which is a big tent grand coalition comprising also the National Liberal Party (PNL). The CNR formerly included the Democratic Alliance of Hungarians in Romania (UDMR/RMDSZ) until mid June 2023.

The National Liberal Party is a social-conservative political party in Romania. Re-founded in mid January 1990, shortly after the Revolution of 1989 which culminated in the fall of communism in Romania, it claims the legacy of the major political party of the same name, active between 1875 and 1947 in the Kingdom of Romania. Based on this historical legacy, it often presents itself as the first formally constituted political party in the country and the oldest of its kind from the family of European liberal parties as well.