The evolution of magnetic cataclysmic variables

The evolution of magnetic cataclysmic variables is reviewed. A simple interpretation of the period distribution of these systems is found possible if their magnetic moments lie in the narrow range 1039 – 1034 Gcm3: systems at long orbital periods are likely to be asynchronous (intermediate polars) and those at short periods to be synchronous (AM Hers). The origins of this field distribution, the inhibition of accretion disc formation, and the synchronization processes are discussed.