Far-left coalition formed by the Portuguese Communist Party (PCP) and the Ecologist Party "Os Verdes" (PEV), incorporating the Association for Democratic Intervention (Intervenção Democrática; ID). Alliance began as the Unitarian Democratic Coalition (CDU), changing its name to "CDU - Unitarian Democratic Coalition" in 2009. Alliance emerged from the dissolved United People Alliance (Aliança Povo Unido; APU) formed in April 14, 1978. Coalition is co-led by the Portuguese Communist Party's general secretary, Jerónimo de Sousa and the PEV's Heloísa Apolónia. Alliance's representation in the Assembly of the Republic was cut in half to 6 seats after elections held on January 30, 2022 [Coligação Democrática Unitária (CDU); aka, PCP–PEV].
