Antonio Gramsci was a leader of the Italian Communist Party in its revolutionary days, and spent almost all his last years in Mussolini's fascist jails. The Prison Notebooks he wrote in jail have been quarried to justify many varieties of reformist or liberal politics. This booklet discusses a major recent study on the Notebooks - Peter Thomas's The Gramscian Moment - and argues that the Notebooks were in fact a powerful contribution to the working-out of revolutionary working-class strategy in developed capitalist societies.