The Progressive Alliance of Socialists and Democrats (S&D) is the political group in the European Parliament of the Party of European Socialists (PES). The Progressive Alliance of Socialists and Democrats was officially founded as a Socialist Group on 29 June 1953, which makes it the second oldest political group in the European Parliament after the European People's Party Group. It adopted its present-day name on 23 June 2009. Centre-left in orientation, the group mostly comprises social democratic parties and is affiliated with the Progressive Alliance and Socialist International.