Stasiology, the science of political parties, has advanced greatly during the present decade. Before 1951, writings in this field had been confined largely to histories of parties, accounts of their electoral fortunes, and discussions of their programs and ideologies. Only two works by Western scholars, both written early in this century, stood out as significant works in analytical stasiology: M. I. Ostrogorski's Democracy and the Organization of Political Parties and Robert Michels' Political Parties: A Sociological Study of the Oligarchical Tendencies of Modern Democracy.