Most existing research indicates that working students perform more poorly than do full-time students on standardized achievement tests. However, we know there are wide international variations in this gap. This article shows that national and international contexts help to explain the gap in the academic performance between working and nonworking middle-school students. We combined data from the 2003 Trends in International Mathematics and Science Study eighth-grade assessment with the countryspecific information on socioeconomic and educational conditions, as well as the timing of each country’s ratification of an international treaty regulating child labor. Our multilevel analyses show that, while student employment is generally negatively associated with academic performance, this negative association is smaller in countries that by 1995 had ratified the International Labour Organisation’s Convention 138 on child labor. These findings highlight the role of national and international policy in structuring the consequences of student employment for academic performance.