1920- . Leader of the French Communist Party (PCF) from 1972. Under his leadership, the party committed itself to a `transition to socialism' by democratic means and entered into a union of the left with the Socialist Party (PS). This was severed 1977, and the PCF returned to a more orthodox pro-Moscow line, since when its share of the vote has decreased. Marchais joined the PCF 1947 and worked his way up through the party organization to become its general secretary. He was a presidential candidate 1981, and sanctioned the PCF's participation in the Mitterrand government 1981-84. He remained leader of the PCF despite a fall in its national vote from 21% 1973 to 10% 1986.