The common wisdom is that when presidential political systems coincide with multiparty systems the result is gridlock; parties squabble and presidents are not able to stitch together the majorities they need to move forward with the business of governing. Latin America’s presidential systems were supposed to have been a disaster. Contrary to the conventional wisdom, however, presidentialism and multipartism seem to work rather well. E pur se muove, to quote Galileo. Over the last decade or so, multiparty presidentialism has become the modal form of presidential democracy, especially in Latin America. Once thought to be a precursor of democratic breakdowns, no compelling explanations have emerged to account for its success in countries such as Brazil, Chile, and Uruguay. The surprising sustainability of coalition-based presidentialism demands an explanation, yet political scientists are ill-equipped to answer this puzzle.