The comparative approach -- Understanding political systems -- Constitutions -- The ideological bases -- Executives -- Legislature, assemblies, and congresses -- Elections and voters -- Political parties -- Political systems of the World's nation-states -- Asia -- Central America and the Caribbean -- Central, Eastern and Southern Europe -- Central and Southern Africa -- The Middle East and North Africa -- North America -- Northern and Western Europe -- Oceania -- South America -- Towards one world -- The relics of empire: colonies, dependencies and semi-sovereign states -- The world grows smaller: international cooperation.