The revolution of 1948 which brought the communists to power in Prague was "passive" in the sense that the groups on the Left which helped it to succeed (socialists, trade unions and rank-and-file communists) had no real part in determining its aims, strategy, or the shape of the regime which followed, for the key factors were the few top leaders of the Communist Party and their links to Moscow. Bloomfield adds a good deal of information to that provided by earlier books on these critical years.