The Trotskyist movement is presented to us as a varied set of militant practices that contain within themselves a way of conceiving their reality and, in addition, incites whoever approaches them to take a position openly favorable or discordant with their ideology.  The main objective of this book is to know how the militant press, proletarian internationalism and transnational sociability facilitated Trotskyism to appear and endure in Mexico as a communist political opposition group.