OECD countries pursue policies to improve the quality and effectiveness of their education systems, but do these policies have an impact on student achievement? International indicators of achievement can answer this question. But developing such indicators has proven a delicate task, both politically and methodologically. Few indicators are currently available, and these cannot be used to evaluate the full range of performance outcomes. This publication recounts the efforts of OECD countries to develop a range of student outcome indicators. It reports on a survey of national education goals and strategies for performance assessment, and argues for broadening the scope of indicators to include general aptitudes and skills, intehered from specific fields such as mathematics, reading, or science.