This paper explores a wide range of determinants of life satisfaction exploiting a database of 73 countries, based in turn on about 100 000 observations. The determinants can be categorized in four groups: political, economic, institutional factors and human development and culture. The relevance of these factors is estimated on country-level averages of satisfaction of sub-groups of national populations according to gender, income and political orientation, using OLS, robust regression and Extreme Bounds Analysis techniques. Our results show that only a small number of factors robustly influence life satisfaction across countries while the importance of a large number of alternative factors suggested in the previous literature is rejected.