In the early twentieth century Russia embarked on one of the most radical legal experiments ever undertaken in a modern state. The essay begins by describing Bolshevik ideas on law and their role in shaping the new legal order. It then moves on to examine the close fit between this legal order and the three institutional pillars of socialism: undivided rule by a Leninist party, a predominance of state ownership of productive property, and a top-down system of bureaucratic coordination. These pillars gave Soviet law its most distinctive characteristic: a tendency for agencies of justice to be subsumed within an overarching system of central management, with its own rhythms and laws of motion. After the Second World War the system of socialist law was transplanted to Eastern Europe. The essay concludes by examining efforts to reform the socialist legal system and by considering its legacy today.