Romanian Social Democratic Party (1990–2001)

The Romanian Social Democratic Party (Romanian: Partidul Social Democrat Român, PSDR) was a social democratic political party in Romania. Founded in 1990, shortly after the fall of the Communist party rule in Romania in December 1989, it claimed to be the direct successor of the historical Romanian Social Democratic Party (PSD) which existed between 1927 and 1948, until it merged with the Romanian Communist Party (PCR) to create the Romanian Workers' Party (PMR).

Joining the Socialist International (SI), the party entered alliances with the Democratic Party (PD; forming Uniunea Social-Democrată or the Social Democratic Union during the 1996 legislative election), and took part in the Romanian Democratic Convention (CDR) governments of Victor Ciorbea, Radu Vasile, and Mugur Isărescu (briefly leading the coalition government with Alexandru Athanasiu as acting/ad interim PM in 1999). The PSDR subsequently adhered to the Social Democratic Pole of Romania (PDSR) for the 2000 Romanian general election, and fused into the Social Democratic Party (PSD) on 16 January 2001.

A minority wing opposed to the merger survived as Partidul Social Democrat "Constantin Titel Petrescu", later reforming itself as the Social-Democratic Workers' Party, but was eventually dissolved in 2013.