In all societies, the family plays a crucial role in shaping the educational experiences and achievement of children and the transmission of status from one generation to the next. Throughout the world, children of high-status parents are more likely to get ahead in school. Three interrelated processes—the transmission of financial capital, the transmission of cultural resources, and the transmission of social capital from parents to children—are most often called on to explain this phenomenon. But only fairly recently have studies begun to incorporate all three processes into empirical investigations of family background in determining children’s educational status. In this chapter, I review the measurement of family background, tracing its increasingly complex conceptualization and examining the methods used to assess the impact of family background on educational outcomes in international and comparative research. Then I assess the quality and content of family background items of past largescale international surveys in detail. Specifically, I focus on several surveys conducted by the International Association for the Evaluation of Educational Achievement (IEA): the Six Subject Study, the First and Second International Mathematics Studies, the Second International Science Study, and the Third International Mathematics and Science Study. I also discuss the Program for International Student Assessment, a current in-