It's a challenge for schools in every country: How to provide the right kind of discipline and create a climate that nurtures learning. This challenge may look different in different countries. A school's disciplinary climate not only is the product of educators' beliefs and actions, students' beliefs and actions, and the interaction of these, but also is shaped by the legal and social context of the country. Yet when they became involved in researching questions of school discipline and the moral authority of teachers, the authors were surprised at the dearth of research comparing various countries' ideas about discipline and typical responses to challenging behaviors. They recently brought together an international group of 18 social scientists to study the relationship between school discipline and student achievement. Their study examined assessment and survey data from 49 countries that participated in the 2003 Trends in International Mathematics and Science Survey (TIMSS), with in-depth case studies of Canada, Chile, Israel, Italy, Japan, the Netherlands, Russia, South Korea, and the United States. The authors compared these countries in terms of how extensive their schools' discipline challenges are, the national context and organizational structure of their schools, and the way discipline is typically administered in schools. The study also examined the relationship between the level of school discipline problems and the level of student achievement--and found a definite correlation between the two. In this article, the authors explore some of what these case studies reveal and reflect on lessons for U.S. educators. (Contains 1 endnote.)