Despite the predictions that consigned it to eternal oblivion, Karl Marx's thought has returned to the limelight in recent years. Marx's Capital, in particular, has been the focus of widespread interest in the wake of the recent international financial crisis. Though among the most important books of the last 150 years, Capital nevertheless represents an incomplete project. More light has recently been shed by the publication in German of Marx's notebooks of excerpts and preparatory manuscripts for the second and third volumes of Capital. However, these volumes are not currently available in English. In this important new volume, Marcello Musto highlights the importance of these texts, and through an analysis of them, aims to reconstruct the stages of Marx's critique of political economy. Similar attention will also be devoted to Marx's 1850s journalism for the New-York Tribune, in which he sometimes dealt with topics beyond those explored in Capital. The book will also consider more carefully some of the most important Marxological debates of the twentieth century, such as those relating to the alleged epistemological break between the early writings and Capital, or to the charge that Engels oversimplified Marx's ideas. It will also be argued that these recently published texts might serve a new political reading of Marx's oeuvre, geared to the understanding and transformation of contemporary society. Through this endeavour, the book aims to provide a more exhaustive account of the formation of Marx's thought than has previously been offered.