Unitary Democratic Coalition

The Unitary Democratic Coalition (CDU – Coligação Democrática Unitária, CDU) is an electoral and political coalition between the Portuguese Communist Party (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 (Intervenção Democrática or ID).

The coalition was formed in 1987 in order to run to the simultaneous legislative election and European Parliament election that were held on July 19 of that year. It achieved its best result in the 1987 elections both nationally and locally. From 1991 until 2019, the party consistently won between six and ten percent of the national vote in elections to the Assembly of the Republic until 2022 and 2024, in which the coalition dropped below 5% nationally for the first time. The coalition supported the minority Socialist Costa Government from 2015 until 2019 with a confidence and supply agreement.

History
Since the beginning of the coalition, the member parties have never participated separately in any election. The Communist Party is the major force of the coalition and has the majority of places in the electoral lists while the Greens are a smaller party. For example, the Greens were responsible for 2 members of parliament among the 17 elected by the coalition in the 2015 legislative election. Each party has its own parliamentary group and counts as a separate party in official issues.

Along with the Left Bloc, the coalition supported the minority Socialist Costa Government from 2015 until 2019 under a confidence and supply agreement. This was known as the "Geringonça" (Contraption) deal, a setup that Prime minister António Costa decided to end following the 2019 elections.

In the 2022 election, the CDU won six seats while the Greens achieved zero seats. In the 2024 election, the CDU won four seats and the Greens zero, with the coalition achieving just 3.3 percent of the votes. In 2024, the coalition lost their historic seat in the Beja district and for the first time lost all MPs in the Alentejo region.

Symbol
The present symbol of CDU shows the PCP's symbol and the PEV's symbol, a hammer and sickle and a sunflower, respectively, with the respective names below. That symbol replaced a former one that featured three hexagons with the inscription: CDU and was often used with a beehive. That was sometimes said to mean that CDU worked just like a bee (collectively and every day) and the hexagons were meant to represent the cell-based Leninist organization of the PCP.

Youth organization
The coalition has a youth wing, called Juventude CDU, that develops political work in youth related subjects, along with youth-oriented activities, mainly during the electoral campaigns. The Juventude CDU is mainly composed by members of the youth wings of the parties that compose the CDU, the Portuguese Communist Youth and the Ecolojovem.

Assembly of the Republic
Vote share in the Portuguese legislative elections