Left-of-center party identified with moneyed interests in São Tomé and Príncipe. Party was launched by millionaire brothers and industrialists Domingo and Antonio Monteiros after they split from the ruling MLSTP in 2018 when it failed to defend the brother's businesses in Angola from seizure (the MLSTP is allegedly linked to the Angolan government). Party began as the Movement of Independent Citizens of Sao Tome and Principe (Movimento Cidadão Independente de São Tomé e Príncipe, MCISTP), changing its name in November 2020 to switch in 'Socialist Party' (Movimento de Cidadãos Independentes - Partido Socialista, MCI-PS). Party has a base in the Caué constituency of the country, holding two seats in parliament from there. Party joined forces with the Partido da Unidade Nacional (PUN) in 2022 ahead of elections held on September 25, 2022 to form the Movimento de Cidadãos Independentes/Partido Socialista/Partido da Unidade Nacional (MCI/PS-PUN) coalition. Coalition managed to maintain the two seats previously held since 2018. Coalition spokesman is Adalberto Catambi.