Over the last century the world has seen several waves of democratization in the developing world. Despite expectations, the quality of these democracies has in many cases disappointed citizens and political onlookers alike. Rather than resulting in accountable and responsive governance, many countries still report high levels of corruption, lowering voters’ trust and satisfaction with democracy. Research has sought to explain why democratic success or backsliding varies across countries, but has focused largely on formal institutions and their ability to constrain behavior, neglecting the role of informal rules and norms in influencing elite corruption in the long term. I argue that the quality of democratic governance following transition depends on the legacy of authoritarian-era informal institutions. When ex-authoritarian elites assume positions of power under democracy, they reproduce the informal rules and norms that structured their past behavior. To the extent that these rules and norms support democracy, elites will pursue accountable governing practices. More often, however, authoritarian-era informal institutions are incompatible with democratic principles and will encourage elites to engage in corrupt, non-accountable behavior. I test my argument using a cross-sectional time series, focusing on young democracies in Europe, Latin America, and Africa. I find that informal institutions are an essential component in explaining quality of governance in young democracies.