This article describes the results of a broad reanalysis of factors shaping the prospects of countries making a transition to or from democracy using a new measure of regime type. While some of the results are consistent with prior quantitative and comparative research, others are not. For example, in line with other studies, the article finds that autocracies are more likely to make a transition to democracy when they offer broader protections for civil liberties, experience a change in political leadership, or suffer an economic downturn. At the same time, the analysis does not support the claim that transitions in neighbouring countries directly improve prospects for a transition to democracy, or that economic decline and presidential systems heighten the risk of democratic breakdown. Perhaps most intriguing, our model of transitions to democracy also identifies a new twist on old stories linking economic development to democratization. For countries under authoritarian rule that have attempted democracy before, the research here indicates that development does improve prospects for another attempt, as modernization theory suggests. For countries with no democratic experience, however, affluence conveys no direct democratizing benefit and appears, if anything, to help sustain authoritarian rule.