This week marks the 75th anniversary of the ‘Barcelona Maydays’ an uprising in response to the Republican Government’s attempt to seize power in revolutionary Catalonia during the Spanish Civil War. Tensions had been building over several months between the anarcho-syndicalist CNT membership and the Soviet controlled Republican army which centred on the questions of militarisation and ‘War or Revolution’? When armed ‘Communist Party’ units attacked the Telephone exchange in Barcelona, thousands of workers responded with an initially ‘successful’ armed insurrection. The Friends of Durruti group were central within this opposition and openly criticised the collaboration of the CNT leadership with the Republican Government. This talk will examine the events of May 1937, why and how the insurrection was eventually defeated as well as the actions and arguments of the Friends of Durruti group. The fundamental question remains ‘should the anarchists have seized power to further the revolution’?