The Class Struggle (Erfurt Program) (German: Das Erfurter Programm in seinem grundsätzlichen Theil erläutert von Karl Kautsky) is an 1892 book-length work by Karl Kautsky.

[2] Eduard Bernstein is acknowledged in the first edition preface as having given advice and critical review.

[3] Historian Donald Sassoon wrote it “became one of the most widely read texts of socialist activists throughout Europe” and Kautsky's commentary “was translated into sixteen languages before 1914 and became the accepted popular summa of Marxism” around the world.

[4] It was first translated into English by Daniel De Leon in 1894 and an adaption published in The People (Socialist Labor Party newspaper) in New York.

[9] Author Lars T. Lih coined the term Erfurtianism to describe the political views put forward in Kautsky's book.