What determines the quality of budget execution around the world, measured in terms of a government's ability to accurately hit its own revenue and expenditure targets? The answers could be relevant to the topics of macroeconomic stability, national development, public service delivery, and political reputation. This paper takes a step toward finding answers through the exploration of a new database of budgets and budget outcomes and potential cross-country correlates of budget execution in levels and in composition. Few countries within the data sample execute their budgets well, in levels or in composition. Expenditure deviations are positively but rather loosely correlated with revenue deviations. Within this broad tendency, there is considerable variation in behavior not only across countries, but also across time within countries. In explaining the cross-country variations, the data confirm traditional drivers for common pool behavior while also supporting constructive roles for political institutions and the technical capacity for public financial management. This is good news for reform minded governments.