The Socialist Workers Party in Greece is an affiliate of the International Socialist Tendency (IST). It is the second largest organisation in IST after the British Socialist Workers Party.

The Internationalist Workers' Left (DEA) (Greek: Διεθνιστική Εργατική Αριστερά) is a Trotskyist organization in Greece. It was founded in 2001 after splitting from the Socialist Workers' Party-International Socialist Tendency (SEK-IST). The organization was particularly active in the Greek Social Forum and the Coalition of the Radical Left. It maintains a sisterhood relationship with the International Socialist Organization (ISO) in the United States. Through the ISO, the DEA has developed connections with both the Socialist Alternative in Australia and the Movement for Socialism in Switzerland.