This book makes a bold contribution to debates on why some South American countries developed strong democracies while others did not. Madrid argues that robust democracies emerged where the military was professionalized, strong opposition parties existed, and ruling elites were divided. This challenges long-held theories that link democracy mainly to economic development, weak militaries, or ethnic homogeneity. In a revisionist view of pre-1930s politics, Madrid shows that while most early South American democracies were elitist and oligarchic, Chile, Uruguay, Argentina, and Colombia expanded suffrage and competitiveness in the early 20th century. Of these, only Chile and Uruguay developed strong democracies. Madrid attributes this to early military modernization – spurred by export booms and interstate wars – which made coups less attractive than democratic competition. Crucially, elite divisions and strong opposition parties also enabled reforms such as expanded suffrage, electoral councils, and voting secrecy. This also explains why Brazil, Peru, and Venezuela became stable autocracies, while Bolivia, Ecuador, and Paraguay remained unstable. A key contribution is Madrid’s nuanced view of the military. While 20th-century coups linked strong militaries to democratic breakdown, Madrid highlights the stabilizing role of professionalized militaries. This connects democracy theory with Weberian state-building arguments about centralization, territorial fragmentation, and war. The book provides rich empirical material, including two original datasets on revolts and historical elections (1830–1929), making it invaluable for scholars of democratization. Two critiques:The theoretical model is highly complex, raising doubts about its applicability beyond South America or after the 1930s. Second, the book’s clear but repetitive structure may tire readers less interested in the empirical detail. Still, Madrid’s work is a landmark study that will shape future research on Latin American democracy.