Using data from the Global Entrepreneurship Monitor (GEM) and the Economic Freedom of the World (EFW) index for 47 countries from 2002 to 2012, we study the multi-level relationship between entrepreneurial traits, market institutions, and individuals’ decision to engage in entrepreneurial action. Our results, which are based on a multi-level fixed-effects regression methodology, suggest that pro-market institutions nurture opportunity- motivated entrepreneurship (OME) on the one hand and reduce necessity- motivated entrepreneurship (NME) on the other. Our multi-level framework furthermore allows us to test the interaction between the macro-level institutional context and the micro-level entrepreneurial traits, attitudes, and behavior. In this respect, we find that entrepreneurs’ knowledge and alertness to new opportunities are more likely to promote OME and less likely to encourage NME, but the strength of the relationship depends on the institutional context. In addition, pro-market institutions seem to exacerbate the negative effect of risk aversion on the decision to start a new venture. These results provide direct evidence that institutions not only channel individual effort to productive entrepreneurial activities, but also enable individuals to more effectively use their entrepreneurial knowledge, skills, and alertness to start new ventures.