The Christian Social Party of Belgium (PSC-CVP) was a Christian democratic political party in Belgium that existed from 1945 to 1968. Founded by Jean Duvieusart in the aftermath of World War II, the party evolved from the Catholic Party of Belgium, and it was Belgium's largest party in most elections, holding 108/212 seats in the Chamber of Representatives at its height in 1950. The party was in government in the 1949, 1950, and all of the governments from 1958 to 1968, allying with the Liberal Party of Belgium on some occasions. In 1968, the party merged into the Christian Democratic and Flemish (CD&V) party.