In Marx’s work, no final presentation of his theory of crisis can be found. Instead, there are various approaches to explain crises. In the twentieth century, the starting point for Marxist debates on crisis theory was the third volume of Capital, the manuscript of which was written in 1864–1865. Later, attention was directed towards the theoretical considerations on crisis in the Theories of Surplus-Value, written in the period between 1861 and 1863. Finally, the Grundrisse of 1857–1858 also came into view, which today plays a central role in the understanding of Marx’s crisis theory for numerous authors. Thus, starting with Capital, the debate gradually shifted its attention to earlier texts. With the Marx Engels Gesamtausgabe (MEGA), all of the economic texts written by Marx between the late 1860s and the late 1870s are now available. Along with his letters, these texts allow for an insight into the development of Marx’s theoretical considerations on crisis after 1865.