Drawing on his experience as a central leader of the Cuban Revolution, Guevara explains why the revolutionary transformation of social relations necessarily involves the transformation of the working people organizing and leading that process. To build communism it is necessary, simultaneous with the new material foundations, to build the new man. Includes Castro?s 1987 speech on the 20th anniversary of Guevara?s death. Ernesto 'Che' Guevara (1928-1967) was an Argentine physician, Marxist revolutionary and central leader of the Cuban Revolution. A key figure in the overthrow of the Batista regime, he held important roles in Cuba's government after 1959, championed internationalist revolutionary causes and wrote extensively on socialist theory and practice. Socialism and Man in Cuba reflects his ideological commitments to socialist transformation and the development of a new collective ethos. Fidel Castro (1926-2016) was a Cuban revolutionary and statesman who led the Cuban Revolution and served as Cuba's head of state for decades; his included 1987 speech situates Guevara's legacy within the broader trajectory of Cuban socialism.