The Radical Socialist Party (Luxembourgish: Radikal-Sozialistesch Partei, French: Parti Radical Socialist) was a progressive Luxembourgian political party that existed from 1925 to 1932. It was the successor of the Liberal League, but, unlike its predecessor, it existed as an organised extra-parliamentary party, marking itself as Luxembourg's first true liberal political party.[1] It was the predecessor of the Radical Liberal Party and, ultimately, of the current Democratic Party.