The study of electoral stability or volatility in Latin America calls attention to profound differences between most Latin American party systems, which are quite volatile, and West European party systems, which remain comparatively stable notwithstanding a trend toward greater volatility in recent decades. The examination of Latin American party systems poses interesting questions about why they differ so markedly from West European systems along this important dimension and what the consequences are for democracy. This paper focuses on volatility in one country, Brazil, in order to examine these issues. I make four arguments: that the Brazilian party system was moderately volatile during Brazil's first democracy (1946-64); that the party system has been highly volatile since 1982; that Brazil's volatility is much higher than that in the advanced industrial democracies; and finally, that the high volatility of the post-1985 period was caused by a combination of structural and institutional factors inimical to strong ties between citizens, political elites and parties, and further boosted by the dismal economic results of 1987-94.