For almost 150 years, scholars have been debating how to interpret Marx’s seminal work Capital while they had access to just some of Marx’s economic manuscripts. This changed in 2013 with the publication of all the known economic writings of Marx and Engels in the Marx-Engels Gesamtausgabe (MEGA). One can now reconstruct the lines of intellectual development, and one can also explore in detail how Friedrich Engels went about compiling volumes II and III of Capital from the vast legacy of manuscripts that Marx left behind after his death in 1883. It should be possible, now, to develop a more comprehensive and accurate picture of Marx as an economic theoretician. This volume of essays aims to initiate this process. Contributors are: Christopher J. Arthur, Matthias Bohlender, Timm Graßmann, Jorge Grespan, Gerald Hubmann, Heinz D. Kurz, Marcel van der Linden, Kenji Mori, Fred Moseley, Lucia Pradella, Geert Reuten, Regina Roth, and Carl-Erich Vollgraf.