Thomas Piketty's Capital in the Twenty-First Century has been hailed as a masterpiece, making a powerful case that wealth inequality is not an accident, but rather an inherent feature of capitalism. But how many of us who bought or borrowed the book have read more than a fraction of its 700 pages? And how many of Piketty's groundbreaking ideas have gone unappreciated, all for want of intellectual stamina? In this handy volume, Jesper Roine – whose own work was relied upon by Piketty – explains in clear and accessible prose the key concepts behind, and controversies surrounding, Piketty's landmark work.