Democratic Unity Coalition

The Democratic Unity Coalition (Portuguese: Coligação Democrática Unitária or CDU) is an electoral and political coalition between the Portuguese Communist Party (Portuguese: Partido Comunista Português or PCP) and the Ecologist Party "The Greens" (Portuguese: Partido Ecologista "Os Verdes" or PEV). The coalition also integrates the political movement Democratic Intervention (Portuguese: Intervenção Democrática or ID).

The coalition was formed for the first time in 1987 in order to run to the simultaneous legislative election and European Parliament election that were held on July 19 of that year.

Since the beginning of the coalition, the member parties have never participated separately in any election. The Communist Party is the major force inside it and has the majority of places in the electoral lists, however, the Greens also have an important presence and elected 2 Members of parliament among the 14 elected by the coalition in the last legislative election. Each party has its own parliamentary group and counts as a separate party in official issues.

At a local level, the coalition usually presents lists in almost every municipality and both Communists and Green may occupy first place on the lists. As the Greens have a smaller structure, the offices of the Communist Party are used as offices of the coalition.