The Accumulation of Capital (full title: The Accumulation of Capital: A Contribution to an Economic Explanation of Imperialism, Die Akkumulation des Kapitals: Ein Beitrag zur ökonomischen Erklärung des Imperialismus) is the principal book-length work of Rosa Luxemburg, first published in 1913, and the only work Luxemburg published on economics during her lifetime.

Her conclusion that the limits of the capitalist system drive it to imperialism and war led Luxemburg to a lifetime of campaigning against militarism and colonialism.

[1] It is in three sections as described below:[2] In the polemic, she argued that capitalism needs to constantly expand into noncapitalist areas in order to access new supply sources, markets for surplus value, and reservoirs of labor.

[3] The Accumulation of Capital was harshly criticized by both Marxist[4][5][6][7][8][9][10] and non-Marxist economists, on the grounds that her logic was circular in proclaiming the impossibility of realizing profits in a close-capitalist system, and that her "underconsumptionist" theory was too crude.

[3] Among Luxemburg's contemporaries, Franz Mehring praised the book as "the most significant phenomemon since Marx and Engels took up the pen" and described criticism of Luxemburg's work, particularly the one left by Austro-Marxists, such as Gustav Eckstein and Rudolf Hilferding, as "one of the crowning achievements of Marxist priesthood.