Theories of Surplus Value is a book that, unlike Marx, actually needs an introduction.
Theories was intended to be collected and published as the fourth volume to Marx's Capital , but after Engels had successfully collected and published volumes two and three after Marx's death, Engels died before he could publish it.
Theories has had a long history of being in-and-out of publication, and particularly in-and-out of being an actually accessible publication.
Pattern Books Theories of surplus value: volume 2, hardcover/karl marx
