Educational technology is often cited as a means to improve educational outcomes and reduce costs, leading to greater quality and efficiency in learning and instruction. Yet research that attempts to assess the costs and benefits of educational technology is limited, making it difficult for educators and policy makers to make efficient decisions. This chapter reviews international research on the effectiveness, costs, and cost-effectiveness of educational technology and provides a set of core conclusions from this literature. The chapter also describes methodological challenges to assessing costs and benefits of educational technology and suggests areas for future research. The chapter concludes with lessons learned for educators and educational decision makers.