Major political and economic shifts have marked the turn into the 21st century: the collapse of the Soviet bloc; the rise to prominence of ecological issues; social changes generated by globalization; and, most recently, one of the worst world financial crises ever. These developments compel us to examine the capitalist system with a critical eye and to reflect on the need for alternatives. The 150th anniversary of the birth of the International Workingmen's Association (IWA) (1864-2014) offers an important opportunity to compare present mainstream paradigms and the political platform developed by the IWA in order to better address our contemporary [crisis?] and theorize solutions. This sourcebook introduces and contextualizes the most valuable notes and proceedings from these legendary meetings, and includes letters and commentary surrounding the events themselves, many appearing for the first time in English. The carefully compiled materials reach beyond Marx's writings through the history of the IWA to include the cooperative movement, trade union reformism, collectivism, and anarchism. In his introductions to these texts, acclaimed scholar Marcello Musto provides accessible critical evaluations and explanations. The text also highlights how certain themes--self-emancipation of the working class versus communist vanguardism and the taking of political power to achieve social ends versus oppressive Soviet-style state control--find sharp discontinuity between Marx's thought as a political leader of the IWA and the tradition of Soviet Marxism. Carefully selected and painstakingly translated, this volume is an invaluable resource for all those interested in the foundations of modern political and labor history.