‘Solidaridad Obrera’ (Workers’ Solidarity), founded in Barcelona in 1907, is the voice of Spain’s Anarcho-syndicalist Confederacion Nacional del Trabajo (CNT: National Confederation of Labour). These essays were issued to celebrate the hundredth anniversary of ‘Soli’ and together they illustrate the changing fortunes of the Anarcho-syndicalist movement, and its enduring attempt to communicate the anarchist idea. Contents: Mateo Rello on ‘Solidaridad Obrera’ 1907-1939: Notes towards a history of CNT journalism, followed by Mateo Rello : ‘Catalunya’, a Catalan-language Soli; Ferran Aisa on ‘Solidaridad Obrera’ 1939-1987: Clandestinity and Transition; Carles Sanz on ‘Solidaridad Obrera’ 1976-2006: A look back at the history of CNT journalism over the last 30 years.