This volume offers an ambitious and comprehensive overview of the unprecedented advances as well as the setbacks in the post-1978 wave of democratization. It explains the sea change from a region dominated by authoritarian regimes to one in which openly authoritarian regimes are the rare exception, and analyzes why some countries have achieved striking gains in democratization while others have experienced erosions. The book presents general theoretical arguments about what causes and sustains democracy in its analysis of nine theoretically compelling country cases.