Barisan Sosialis

Barisan Sosialis (BS), also known as the Socialist Front, was a left-wing political party in Singapore. It was formed on 29 July 1961 and was officially registered on 13 August 1961 by the leftist faction of the People's Action Party (PAP) which had been expelled. The prominent founding members of BS were Lee Siew Choh and Lim Chin Siong. It was one of the biggest opposition parties in Singapore during the 1960s. It listed its main objectives as "eradicating colonialism", establishing a "united independent and democratic Malayan nation" comprising the Federation of Malaya and Singapore, and "introducing an economic system to promote prosperity and stability in society."

As the PAP consolidated its power during the 1960s, the PAP-led government cracked down on BS, accusing it of pro-communist activities as part of the geopolitical climate of the Cold War. In 1963, as part of Operation Coldstore, over 100 opposition leaders, including Lim, were arrested in preventative and indefinite detention under the Internal Security Act (ISA) with support of the British and Malayan governments. The arrests severely weakened BS, with boycotts by BS MPs to Parliament leading to more arrests throughout 1966 and 1967, most notably Chia Thye Poh. BS would fully boycott the 1968 elections, cementing PAP political dominance. These crackdowns were justified by the government as a security measure to prevent a communist revolution; Chia himself declared that the means of the struggle would be "street demonstrations, protests and strikes". However, the political crackdowns were also criticised as political suppression, as BS members did not publicly agitate for communism or subversion.

Despite contesting subsequent elections, BS never recovered from its heyday and most of its members joined the Workers' Party (WP) in 1988. An application for dissolution was denied and the party became dormant. In 2025, it was officially deregistered alongside 13 other parties for a failure to prove its existence while inactive.