The Trotskyist movement does have a significant record of achievement in the field of social movements. This chapter begins by recapping the main features of the movement before proceeding to summarize its intrinsic weaknesses and limitations. Trotskyist organizations are hybrid bodies combining elements of the political party, the sect and the social movement. In general, the Trotskyist movement embodies a paradoxical combination of exceptional levels of organizational resilience combined with persistent failure to achieve its major goals because of doctrinairism and sectarianism. The most striking achievements of the Trotskyist movement are to be found in the field of social movements. One of the most striking failures of the world Trotskyist movement and that is the absence of any revolutionary struggle led by Trotskyist forces. One final weakness of the Trotskyist movement is a persistent inability to engage in critical self-reflection, a trait more obvious in some families than others.