Volume 9 is the last in the group of volumes (7-9) covering the activities of Marx and Engels during the revolutions of 1848-49. It encompasses the period from March to August 1849 and consists mainly of articles written by Marx and Engels for Neue Rheinische Zeitung, an organ of the revolutionary proletarian wing of German and European democracy. This volume also contains several articles which Marx and Engels published in the still surviving German democratic newspapers when Neue Rheinische Zeitung was suppressed. The material presented in this volume enables researchers to trace the new features which appeared in the strategy and tactics of Marx and Engels at this stage of the revolution with their endeavour to bring about the organisational separation of the working class from the democratic movement in general, and to create a political mass party of the proletariat. The appendices in this volume throw further light on the new aspects of their practical activities during the period of growing harassment of the democratic working-class movements and their newspapers.