Democratic Left (Italian: Sinistra Democratica, SD), whose complete name was Democratic Left. For European Socialism (Sinistra Democratica. Per il Socialismo Europeo), was a democratic-socialist political party in Italy.

SD was founded on 5 May 2007 by splinters of the Democrats of the Left (DS) led by Fabio Mussi and Gavino Angius, who opposed the merger of the DS with Democracy is Freedom – The Daisy to form the Democratic Party. According to its leading members at its foundation, SD was to be not a party but a movement, with the goal to unite the entire Italian left from Communist Refoundation Party to the Italian Democratic Socialists.

On 22–24 October 2010, SD was merged into Left Ecology Freedom.

In April 2007 the Democrats of the Left (DL) held in Florence their last congress in order to ratify the move towards the foundation of the Democratic Party, along with the centrists of Democracy is Freedom – The Daisy. In opposition to Piero Fassino's majority resolution, two resolutions were tabled by supporters of the factions led by Fabio Mussi and Gavino Angius (who formed Socialists and Europeans together with Mauro Zani): the first opposed in any form the foundation of the PD, whilst the second was favourable only in the event that the new party was to join the Party of European Socialists and thus represented a more "wait and see" attitude. These resolutions managed to garner around 25% of the vote.

Following the congress, a large majority of Mussi's followers, with a few notable exceptions such as Vincenzo Vita, left the DS. This was consistent with their declared position prior to the Florence congress. In contrast, Angius' sudden departure from DS after the congress was somewhat surprising and arguably inconsistent with the position adopted by the supporters of the Angius-Zani resolution prior to and during the congress itself. Consequently, rather than follow Angius out of the party some of the most significant supporters of the motion, including Zani, Massimo Brutti and Sergio Gentili opted to stay inside the DS. On 16 May 2007 the new party's parliamentary groups had 22 deputies and 12 senators.

Following its foundation, SD was divided between supporters of Mussi, who wanted strong relations with the so-called "far-left parties" (Federation of the Greens, Party of Italian Communists and Communist Refoundation Party), and those around Angius, who were keener on an alliance with the more centrist Italian Democratic Socialists. In September Democracy and Socialism, led by Angius and Valdo Spini, joined the "Socialist Constituent Assembly" and committed themselves to the foundation of a social-democratic party in the tradition of the historical Italian Socialist Party. Finally, in October 2007, Angius and his group left SD to found the Socialist Party.

The SD party suffered another split in February 2008 when Famiano Crucianelli, Olga D'Antona, Paolo Nerozzi, Massimo Cialente and Gianfranco Pagliarulo (a former member of the Party of Italian Communists) abandoned SD in order to join the Democratic Party, through an association named Left for the Country.

In the 2008 general election The Left – The Rainbow, of which the Democratic Left was a part along with the Communist Refoundation Party (PRC), the Party of Italian Communists (PdCI) and the Federation of the Greens, gained 3.1% of the vote and failed to win any seats in the Italian Parliament.